Well, in Japan at least. Street Fighter IV is indeed getting a proper arcade version. Japanese magazine Famitsu was able to confirm that with Capcom. The game will hit Japanese arcades sometime this year. Kinda sad that we live in an age that we must worry whether or not arcade-style games will actually appear in arcades — even in Japan! Now, which arcade hardware the game will appear on isn't yet known, but as game site arcade Renaissance points out, Capcom is currently using the System 256 hardware for Sengoku Basara X. Another thing that isn't yet known: What home platform (or platforms) the game will be appearing on. Looking at Capcom's recent M.O., we're expecting Xbox 360, PS3 and PC.
SF4 Confirmed [IGN via Arcade Renaissance]