I don't know what happened to him... then again I'm guessing he's from the 1986 - 1996 cartoon, which I never payed much attention too; liked the comics more. Plus if you like big guys, you should see the Garbageman from the new cartoon.
I do'nt know enough abou TMNT to say much... I like the new cartoon series better than the old one , and did'nt even read any comics. What I have seen of the new series had dumb jokes, bad animation, and terrible plotholes galore. The movie(s) were O.kay though.
TMNT wouldn't be TMNT without dumb jokes. I didn't notice any plotholes, except the whole "going to the future thing" (aka Fast Forward), going back in time should be really easy, all they need to do is call that time-traveling guy, Lord Simultaneous and poof, they're problems are gone.