short version: don't worry about SOI, just know that its good 
longer version for techheads:
http://news.teamxbox.com/xbox/6201/SiliconOnInsulator-to-Power-Xbox-2-Processor
http://www.ps3rumors.com
http://www.totalvideogames.com/pages/articles/index.php?article_id=5953
http://www.siliconstrategies.com/showArticle.jhtml?articleID=22102313&_requestid=525698
please forgive me Nintendo fans. your Revolutionary 'Revolution' will also likely enjoy the benifits of SOI.
longer version for techheads:
http://news.teamxbox.com/xbox/6201/SiliconOnInsulator-to-Power-Xbox-2-Processor
Silicon-On-Insulator to Power Xbox 2 Processor
By: César A. Berardini - "Cesar"
Jul. 1st, 2004 03:04 pm
According to Pascal Mauberger, Chief Operating Officer of Soitec, IBMs silicon-on-insulator (SOI) semiconductor technology will be used in both the Microsoft Xbox successor and Sonys PlayStation 3.
"SOI is in Xbox through IBM. It is in the Sony PlayStation. And we will soon have three 300-mm wafer fabs producing SOI," Mauberger told Silicon Strategies. "IBM East Fishkill is running 90-nm SOI. Sony's Nagasaki plant is due online by the end of 2004," he added.
Soitec is a manufacturer and provider of SOI wafers. The silicon-on-insulator is an advanced semiconductor manufacturing technology that produces higher performing, lower power processors than traditional silicon techniques.
This SOI technique speeds the flow of electrons through transistors to increase performance and provides an insulating layer in the silicon that isolates transistors, decreasing this way the power consumption. The technology allows manufacturers to fabricate higher clocked processors while lowering the power demands of the components.
A real example of SOI is IBMs Power Architecture microprocessors, found in Apples PowerMac G5 computers and in Xbox 2 alpha SDKs. While processors from Intel or AMD consume as much as 100W (you might have seen that big heatsink inside your PC), IBM's current PowerPC 970FX chip consumes about 50 watts in its 2.5GHz version. The previous PowerPC 970 processors, manufactured on a 130-nm process, required 66 watts at a lower clock speed.
They Are Everywhere
There is one thing that Sony, Nintendo and now Microsoft have in common: IBM. The Big Blue, Sony, and Toshiba partnered in 2001 to develop the "Cell" technology that will power the PlayStation 3 among other consumer electronics. IBM also provides the Gecko processor used in the Nintendo GameCube and industry insiders have revealed that Revolution will also use an IBM processor.
Who is the last one to join the party? As TeamXbox revealed in a world exclusive, IBM is the technology partner Microsoft chose to build a state-of-the-art processor for the Xbox successor that is supposed to be a multi-core CPU, capable of processing six threads simultaneously. This processor might also be the first PowerPC built on a 65-nm process, as we informed in this previous story.
Since IBM is the pioneer in silicon-on-insulator technology, it is a no-brainer that all these processors will be built using SOI as well as other IBMs technologies.
Stay tuned, well have more on Xbox 2 soon.
http://www.ps3rumors.com
PS3/Xbox2 to utilize SOI technology? : A report in Silicon Strategies today suggested that both Sony and Microsoft will be utilising new technology when designing the processors set to feature within PlayStation 3 and Xbox2. Silcon-On-Insulator (SOI) is a new approach in which transistors are built on top of an insulating material instead of the conventional silicon crystal substrate; the result is transistors that can switch faster with lower power consumption, although the technology still suffers from erratic issues. Speaking to Pascal Mauberger CEO Soitec SA, a leading manufacturer of SOI technology, Mauberger refused to comment on specific details but did claim "SOI is in Xbox through IBM. It is in the Sony PlayStation. And we will soon have three 300-mm wafer fabs producing SOI," Mauberger told Silicon Strategies. "IBM East Fishkill is running 90-nm SOI. Sony's Nagasaki plant is due online by the end of 2004 and AMD's next Dresden fab is due by the end of 2005," he added. [Jun-28-04]
http://www.totalvideogames.com/pages/articles/index.php?article_id=5953
Xbox 2/Playstation 3 Utilise SOI Technology???
28/06/2004
By: Chris Leyton
A report suggests that both Sony and Microsoft will be using new transistor technology in the development of Xbox2 and Playstation3
A report in Silicon Strategies today suggested that both Sony and Microsoft will be utilising new technology when designing the processors set to feature within Playstation3 and Xbox2.
Silcon-On-Insulator (SOI) is a manufacturing approach in which transistors are built on top of an insulating material instead of the conventional silicon crystal substrate; the result is transistors that can switch upto 15% faster with 20% lower power consumption - something that will help if Microsoft plan to stack three PowerPC processors.
Speaking to Pascal Mauberger CEO Soitec SA, a leading manufacturer of SOI technology, Mauberger refused to comment on specific details but did claim "SOI is in Xbox through IBM. It is in the Sony Playstation. And we will soon have three 300-mm wafer fabs producing SOI," Mauberger told Silicon Strategies. "IBM East Fishkill is running 90-nm SOI. Sony's Nagasaki plant is due online by the end of 2004 and AMD's next Dresden fab is due by the end of 2005," he added
http://www.siliconstrategies.com/showArticle.jhtml?articleID=22102313&_requestid=525698
SOI set to drive Xbox, PlayStation, says Soitec exec
By Peter Clarke
Silicon Strategies
06/27/2004, 12:59 PM ET
LONDON -- One indicator that silicon-on-insulator (SOI) technology is entering the mainstream is that the technology is set to be used in future generations of both the Sony PlayStation and the Microsoft Xbox, according to Pascal Mauberger, chief operating officer of SOI wafer provider Soitec SA (Grenoble, France).
And design wins for SOI in the games market come on top of a design-win for the technology in the computer space, in the form of the 90-nanometer version of the Opteron processor from Advanced Micro Devices Inc. (AMD), Mauberger said.
AMD began using a 90-nanometer silicon-on-insulator (SOI) manufacturing process on 200-mm diameter wafers at its Fab30 in Dresden, Germany, in April. At the time AMD said it expected to ship commercial products in the third quarter of 2004.
However, one significant chipmaker not committed to using SOI technology is chip market leader Intel Corp.
With success built on a leading position making microprocessors for PCs Intel is usually guarded about its manufacturing processes and any changes it makes. It also has reputation for pushing established technologies further than others and being cautious about potentially risky technology changes.
For Intel -- and the rest of the industry at present-- the conventional starting point for silicon chip manufacturing is a monocrystalline wafer of pure silicon. The standard technology for digital circuits is then to lay into and onto this wafer complementary p- and n-type transistors and metal interconnect in a design and manufacturing style called CMOS. But Soitec's Mauberger argued that with the 'Cell' processor in development at Sony targeted at 65-nm SOI manufacturing process and with IBM set to make an SOI-based contribution to a future version of Microsoft's Xbox games console, SOI CMOS technology is gaining traction in the industry.
Soon CMOS built into and on top of a thin layer of silicon above an oxide insulating layer could become the standard way of making integrated circuits, something which would benefit wafer supplier Soitec greatly.
The extra complexity of creating the SOI wafer, the task that Soitec handles for its customers, is generally acknowledged to result in reduced leakage currents and increased performance. However, SOI has not yet been used for many high volume circuits and has been deployed mainly for its ability to proof a circuit against radiation-induced errors.
With the increasing need to increase computational and power efficiency many technologists have agreed that SOI is the future of digital electronics (see CTO interviews here and here) but many have also disagreed about when the SOI era would begin. Some have said the change over to the SOI technology is imminent, while others have said it will remain on the sidelines as a high performance option that many would choose not to pay for, leaving 'vanilla' CMOS as the industry-standard starting point.
Mauberger argued that the successful deployment of SOI in the games market, which combines high production volumes with high performance needs and consumer electronics price sensitivity, would give it economies of scale to help it succeed in other markets.
"SOI is in Xbox through IBM. It is in the Sony Playstation. And we will soon have three 300-mm wafer fabs producing SOI," Mauberger told Silicon Strategies. "IBM East Fishkill is running 90-nm SOI. Sony's Nagasaki plant is due online by the end of 2004 and AMD's next Dresden fab is due by the end of 2005," he added.
In fact IBM's close alignment with AMD, Toshiba and Sony means that the imminent deployment of SOI could be seen as a struggle between an IBM view of the world and an Intel view of the world.
If IBM is right and advanced chip production needs SOI while Intel is slow to adopt the technology, then IBM, and those that adhere to its view, could prosper while Intel suffers.
It is notable that Xenon, the codename for the Xbox follow-on games console due to appear in 2005, is to be powered by a processor with three PowerPC processor cores on the die each operating independently at clock frequencies in excess of 3.5-GHz, according to reports. The triple PowerPC processor was designed by IBM in close co-operation with Microsoft's Xbox team, the report said.
IBM's design win within Xenon or Xbox2 does represent a success for IBM at Intel's expense (see November 2003 story). Mauberger would not confirm that this particular design was the SOI target. "All I can say is that Microsoft has placed a contract with IBM for SOI," Mauberger told Silicon Strategies.
Of course, it is quite possible that Intel will roll out SOI or strained silicon technology with a flourish and hit the ground running when its customers need it. From being apparently behind in the process technology stakes Intel has often proved to have been correct in its reticence to adopt a new technology or to have been quietly developing a leading position without needing to talk about it.
But until then IBM, Soitec, and other supporters of silicon-on-insulator would appear to be making the play.
please forgive me Nintendo fans. your Revolutionary 'Revolution' will also likely enjoy the benifits of SOI.