SF does indeed evolve more with each game. Guilty Gear was pretty much a run-of-the-mill 2D fighter with metal music, cool characters and an awesome story. But however it did have good things that other 2D fighters didin't have, like you can use the tension gage for more then just supermoves. I still think GG and SF reign surpreme over all games to date.

Anybody notice how KOF games, dispite using the same graphics engine sence 1993 have added new things to their games every time?