It was known for quite some time that the live arcade service would be the latest battle ground for two of the biggest fighting franchises to duke it out.
Capcom launched first in August with Street Fighter II which came out to mixed reviews. It seems that everyone complained about something, if it wasn't the 360's D-pad, it was the lag, if it wasn't the 4:3 aspect ratio, it was people using the hundred hand slap. The good news for Capcom though, was that it sold like crazy, quickly becoming one of the fastest selling XBLA games to date.
According to Gamespot, Midway will be launching Ultimate Mortal Kombat 3 this November. Will they learn from the mistakes of their foe and have spotless online multiplayer? It's certainly far to early to tell. From the screenshots I've seen, they seem to have gone with the wide screen aspect ration which should quite a few detractors (although how this will change the game dynamic is yet to be seen).
I for one bought SFII and will happily buy UMK3 and if it weren't for the fact that I regularly get my butt handed to me by people who have barely ever played the game, I'd challenge you all :)
You can check out Gamespot's story here.