One of the selling points for this film was how it was shown using “InTru3D.” As such, it was a must for me to see this film in 3D. I have to say that I was impressed. I think it was partially because it was a CGI movie, but the 3D was really seamless and seemed natural, and they weren't (m)any cheap sight gags.
As for the film itself, I believe it's goal was to be a throwback to classic sci-fi films and there were even references that only the knowledgeable would catch (i.e. the reference to Close Encounters of the Third Kind).
I also enjoyed the voice acting. Seth Rogen was funniest, Hugh Laurie was probably my favourite, and Kiefer Sutherland was near unrecognizable.
The film doesn't come close to the sheer awe of Wall-E last year, however it was still a fun animated sci-fi/action film and it's definitely the best animated film of the year so far.