There are no official fighting game titles for PC but theres THIS.
If anyone is even remotely a serious fighting game player, or you want to test your skills against people, check this out.
http://ggpo.net
"GGPO.net is a new approach to online fighting games. Traditional networking algorithms used to compensate for network latency result in either slower than normal gameplay or an excessive amount of delay (or lag) tacked onto the beginning of each move. GGPO.net uses a novel way to hide latency which lets the game run at full speed without adding any delay to any of your moves. So your timing doesn’t change and combos come out like butter. It’s almost like playing head-to-head in your living room!"
You can play Street Fighter Alpha series, Marvel vs Capcom, Darkstalkers, KOF98, Super Street Fighter 2 Turbo, etc...
Let me tell you one thing, this is BY FAR BETTER than any online fighting game released to date on any console. Input lag kills gameplay for fighting games and it was thought to be impossible to play normally online, but ggpo is actually playable. Sure, not perfect 100% offline emulation but close enough to play serious. Even hardcore offline players are seen on ggpo playing so that's definately saying something about this. Fighting game Devs should learn from ggpo.
crappy old school NES games are more entertaining than next-gen games.
