Okay, there are two characters over at IMDB I have no idea about:

1. "Mouse" played by Joseph mazzello

2. "Havoc" played by Matt Gerald

I know that the HAVOC was a 1986 toy, and that the movie studio is most likely just taking liberties by turning a tracked-vehicle into a person (God knows there aren't enough characters in the G.I. Joe universe, that they have to go and turn a vehicle into one for plot progression), but is it just ME or is "Mouse" not in the G.I. Joe lore at all (at least not in the Marvel or Sunbow part of it)?

Anyone know?

See that's how you kill a franchise by "f"ing all up. Mouse? come on, you could have used TunnelRat. Rely on the big guys first and keep it small. That's Hollywood for you, bunch of useless suits.

http://toynewsi.com/news.php?catid=9&itemid=17523 Its a total new character... And for Havoc.. might read http://generalsjoes.com/2011/08/22/...by-matt-gerald/

also rumored ok NOT rumored now that Bruce Willis will do a small part and play Joe Colton in it.
G.I. Joe 2: Retaliation (2012)
www.imdb.com
Directed by Jon M. Chu. With Bruce Willis, Channing Tatum, Dwayne Johnson, Adrianne Palicki.

So far its sounding a lot better and more star power than GI Joe 1......

and lets not forget the Live Action HISS tank is supposed to be in the movie or so John Chu rumored on his blog/facebook page...

Wasn't Mouse a character from GI Joe Extreme, or something?

pretty sure mouse was a hacker the Joes used in the devil's due comics

http://toynewsi.com/news.php?catid=9&itemid=17905 Some vids and yes Bruce Willis shots in the movie...