The good thing about it is that the 4 Turtles themselves are such strong archetypes that it's really hard to mess them up too badly.
And while I'm not naturally a Megan Fox fan, my inner 8 year old succumbs just a little bit when I see her wearing yellow.
My biggest concern is how the Turtles will look. I'm having a really hard time wrapping my head around CGI Turtles in a live action movie. I'll have to see them in action before I can render an accurate judgment.
As for the previous movies, I really love the 1st & 4th ones. The 1st one is great because it's so dark & adult. The 4th one really amps up the action levels in a way that the live action ones couldn't really accomplish. Plus, I love the way the 4th one brings the conflict between Leonard & Raphael to a head. Frankly, I wish that they had just continued with more CGI movies following the 2007 film rather than this new reboot.
The 2nd movie isn't quite as good as the 1st & 4th ones, but I loved it as a kid and I can't help but still love it now.
The 3rd one is a bit too watered down & kidded up. A lot of interesting story threads get introduced but never followed through on. But at least it's a unique setting & story compared to the others. I'll call it a guilty pleasure at least.