I know GameFAQs isn’t generally looked highly upon here, but they have a 2D fighter-related poll today (June 22nd), so I figured I’d let people know about it. Their choices are reasonably comprehensive, and the results are pretty revealing, for what they’re worth. Could explain why Midway keeps making MK games, at least.
PS I voted Darkstalkers. Yeah, SF may have the better games, but there’s that certain level of character, atmosphere and charm that DS has in spades.