I hated it for several reasons:
1) change of character moves
2) weird sorta kinda 3d backgrounds which spin as you move :S
3) Crap story mode
4) crap boss
5) weird and useless interactivity in backgrounds i.e sheep being kicked around. Should have made it like def jam ny where u can manipulate the objects to your advantage.
IMO, SF4 done a fat better job than tekken6, but then again, I always preferred SF over Tekken