I don't think Russell Crowe can't sing. It's just I feel his voice isn't intense enough for the part that Javert seems to be.
I watched it on the 27th for my sister's birthday and I liked it a lot. While I was slightly annoyed cause it wasn't exactly like the 10th anniversary version which I watched as a wee boy, I feel like it was filmed very well and the style of recording (on the spot as opposed to recording it) did indeed help in invoking more emotion in scenes.
I also like how Colm made a reappearance, being the most legit Valjean that I know.