So far, the obvious plus the ones people have pointed out to me:
1. Bowser
2. Eggman
3. Zangief
4. M. Bison
5. Zombie (from House of the Dead 2, supposedly)
6. The purple rhino from Altered Beast (forget his name)
7. Q-Bert
8. Clyde (from Pac-Man)
9. Paperboy (You can only see him briefly)
10. Someone from Mortal Kombat (I don't remember the name but people are claiming he's visible in the trailer)
The promotional stills for the movie also show the following:
11. Chun-Li
12. Coily (Q-Bert)
13. Ugg (Q-Bert)
14. Wrong Way (Q-Bert)
15. Sam (Q-Bert)
16. Slick (Q-Bert)
...and that's all I know of.
To be quite honest I'm not all that impressed with this movie. It's nice they got the rights to feature these characters but if they're just gonna appear for one scene and maybe deliver a (rather cheap and corny) gag than that doesn't give this anymore weight than your average sprite comic or Robot Chicken sketch. Other than the video game hook this film's premise looks like a lame repeat of Megamind, yet I see people praising it everywhere. Some even compare it to Roger Rabbit (something I cannot understand, since it looks like the amount of "love" for video games here pales compared to the tribute they paid to classical animation there), or Toy Story (which once again is hardly an apt comparison considering Toy Story at least gave certain well-known toys some important roles while this movie appears to just use the game characters for throwaway scenes).
Also, you all know [darn] well that Disney is gonna make this their next merchandise juggernaut.... and people will likely eat it right up.What does it say about the state of video games in the public eye when what essentially amounts to a copyright safe parody of Mario and Donkey Kong winds up eclipsing the real thing? How is it that we finally get a proper animated movie featuring game characters with some honest effort behind it, and the end result is a premise we've seen a million times before (a meta-parody, for those couldn't figure it out)?