Saw it last night. It was a late show, I was tired, and I got pretty bleary toward the end. I gave it an 8 as a result to be generous, but honestly I don't think it was all that. The pacing was off. Too slow, lack of tension, and not enough shooting up giant robots with P40's.
There was also a bit of a hole in the story development. I mean, giant robots FILLED the skies but what did they really DO? Tore up a few streets and step on a few cars. I just thought it needed a little bit more to generate care and concern from the viewer for the protagonists. Character introductions and development got pretty short shrift too - but that's a fairly "old-fashioned serial" thing so I can write it off as being a style decision.
Visually fantastic, though I'd have preferred either more color or less - the light colorization was actually a bit distracting for me. Should have actually been sepia-tone as was (IIUC) the original intent.
Not as great as I really wanted (especially after waiting through the interminably delayed release), but I want a sequel.