If you have any affection for U2, or have never been to a real rock concert, or it's just been a while since you've heard loud music (and you like that sort of thing), I strongly urge you to see U23D. See it in all of it's IMAX 3-D glory, if at all possible.
U2 is a great band - the fact that they are now billionaire activists for Peace, Love, Justice, and all that stuff makes it all the easier appreciate that it's what they were about, all along. It's been cool to watch them grow into what they've become.
I had the pleasure of seeing the "Vertigo" tour twice. In many ways, this film is about as close as one could come to being there - in many ways, better - because the camera takes you onstage. Having been to these concerts, the film brought back a lot of the emotional substance. I don't know if one can really get the sense of what it is to see, hear, and feel an arena full of people dancing and singing In the Name of Love at full throttle, but you should at least be able to appreciate the moment in the film when Bono steps back from his mic and says, "Wow!" I am usually taken by The Edge's powerful solo lines, and the movie certainly provides those opportunities. They are veteran performers, but this movie also brings you into the circle, a bit, to see that they are still having a very, very good time.
The 3D is good, really good. There's some gimmickry, mic stands standing out, shots of Adam poking his bass neck around like he's probing a large, wet balloon - no, wait, he always does that. Larry Mullen's drum kit looks phenomenal through the polarized glasses. You can also see how hard he's working, something you tend to forget when watching him from a quarter mile away.
It has been a very long time since I've been 'wowed' at the movies. I knew that I was going to like the music, but the 3D really did make it a 'wow' experience. Don't wait for this to come out on DVD - I don't think it'll be quite the same. It's like the difference between listening to music in your living room vs. seeing it performed live. Except different.