It's pretty good, but don't expect the reinvention of cinema they promised you.
The 3D effects are great, but hardly used. Mostly they're used to show distance/perspective.
The directing wasn't very good overall. I had the impression that I missed interesting moments because the cameras caught something else. Also, major parts aren't filmed from the front but the side. The cuts/effects to get from one song to the next are horrible, every amateur with a camcorder can do better. Everyone who bashed Hamish Hamilton and praised Catherine Owens should apologize.

The great crowd is barely audible (with some exceptions). The band's performance isn't really passionate, they just do what they get paid for. But that's something we knew already from the DVD.
At the end of the day, the movie is pretty cool but nothing you should loose sleep over, you get some amazing Larry shots, during some moments you really feel like you can touch Bono. The 3D effects are really cool during Love and Peace and The Fly but there are also the negative points I mentioned.
I'll have to watch it again in a cinema packed with U2 fans, but for now it's a 7/10 in my book.