Over 2500 hours in Diablo 3 for me so I'm very very excited but I fear it will be fucked in some way, best case I think it'll be like D3 at launch and take 6 months to be properly great and maybe even first expansion/2.0 patch to be the final game with proper synergies and the like.
Just when I saw their passive tree last year (which was literally a tree... morons lol) it looked like they have no idea what they're doing, like D3 was at launch. I have no faith they won't just put out a game having learned nothing from how D3 changed going from 1.0 to Reaper of Souls/2.0 and beyond, Inferno was unplayable at launch and not even because of RMAH, it was just terribly balanced.
It'll be like: "Heres the best set in the game, when you wear all the pieces you get TWO HUNDRED PERCENT DAMAGE. Pretty sweet eh?"