The 3D was okay for the space/Oa sequences, since most of that was all CGI anyway, it was much easier to tweak it for 3D viewing.
I couldn't believe how cheap the earth-side scenes looked, as most of it looked like they were shot on studio stages with that that certain "look". Most scenes...
The space/Oa stuff was fun (in 3D), the earth-side stuff was stiff and uninvolving (flat in 3D). I think kids will enjoy the spectacle and comic-book sensibilities. Chemistry between Reynolds and Lively was so-so. The script is haphazardly plot-driven with wide jumps from scene to scene...