"Ask a ninja" ninja would be hilarious in poker, especially if Guybrush/something piratey were also at the table. But he's not computer/cartoon graphics. Oh well.
Bender from Futurama is the one dream character I would choose above all others if I could choose literally any one comic/cartoon/videogame character.
But Sam and Gabe seem like almost certain choices if new characters are added.
What would happen if Minsc and Boo from Baldur's gate were at the table? Would he (so he claims) be getting advice from Boo or just go bust on round one and go for the eyes?
I suspect that the Tick is too stupid to play poker, but it sure would be funny while it lasted.
Invader Zimm might be fun.
And Glados. Yes. Not sure why "she" would be playing a poker game, but I'm sure there's some great dialogue in there somewhere. We already know Valve is apparently willing to work with Telltale with the Heavy. I'd like to see Alex from HL in the game (or, well, just see Alex, period,) but she might be too "realistic" to function with these jokers.