I suspect the TMNT movie is a bit of a reinterpretation/evolution of the original story. Which is what they'd HAVE to do to get it to work. No one would want a remake of something everyone's already seen ages ago.
Same with the Transformers movie. It looks weird.
Hope they do something nice with the TMNT 360 game, though, it looks to have a LOT of potential... but I have a weird feeling it'll turn out mediocre...