Ed Boon was at the end of GameSpot’s coverage of the annual convention demoing the game with Paulo Garcia and John Edwards playing 3 fights (one of them in tag team mode) with fatalities at the end of each, just watch the video, anything I say won’t be enough to describe it:

I’ll update this post with more facts and some screenshots for the section of the game.

Mortal Kombat Online has a lot of facts about the game summed up in this article, be sure to read it and check the hi-res screenshots.