I don't think this is such a big problem for Microsoft. We still don't have actual confirmation of these damning rumors. Besides, things can easily change in an instant, and it seems like we won't need to wait much longer anyway. For all we know, the always online stuff may have been taken out of context; there may be exceptions to it. Although, I expect BC will not be available which sucks for a lot of 360 owners out there who would like to trade in their consoles toward the purchase of the Xbox and/or get rid of console clutter.
I'm not saying Xbox 720 will be a bag of sunshine and rainbows (every console has its share of issues), but I don't think Microsoft will completely shoot itself in the foot like some of these rumors are suggesting it has. We shall see.