(This is all taken from the PS3 beta, Dec 2010. The full game will be available January 11, 2011.)
I first encountered Ambush Bug in DCUO shortly after hitting level 6 as a villain character. I completed a mission and received a surprise communication from Ambush Bug. He talked and everything! I was in shock. Here's his mission screen:
Ambush Bug "hosts" a zone where you can get free daily prizes. Once you activate his ticket, you can visit the Vault just to see what items and cash you can collect. Ambush Bug does not actually appear in the Vault... in fact, the Vault's voiceover is done by the Joker. So it's a little weird that he fronts this, but whatever, THIS IS THE FIRST ANIMATED, VOICED AMBUSH BUG IN OFFICIAL DC MEDIA EVER. Awesome.
You can find Ambush Bug standing around in the Hall of Doom (does he also perform the same Vault function for the Heroes?), right beside Catwoman, of all people. He has some cute repeating animations where he laughs heroically and scans the surrounding area.
His costume - presumably designed by Jim Lee since just about everything else in DCUO is Lee's handiwork - is a neat take on the traditional green bodysuit. His costume bunches up at the extremities, giving the appearance of a slipshod fit. The yellow piping on his mask echoes a moustache/goatee more than usual. When you talk to him, you get his canned Vault speech.
DCUO is definitely going for the madcap, original Bug... which is appropriate since his string of Doom Patrol appearances has also been in that vein. Note that, as usual, Irwin is aware of his reality: he's inside a video game.
My PSN name is StocDred if you're in DCUO and want to partner up!