I mostly bought this for David Arnold's score. Track 22 is a 23-minute long suite containing all of his film music and, like his James Bond soundtracks, it's brilliant.
I was expecting to skip most of the rest but in fact really enjoyed it. Piles of 70s and glam, a pretty solid compilation album- you can't go wrong with XTC and T-Rex and The Troggs.
Some of the newer music, from bands like The Fratellis and Supergrass, I didn't enjoy so much (it's difficult for them to compete with Adam Ant and The Sweet), though Jon Spencer's contribution is really good.
Each track is smoothly linked together (by music editing genius Osymyso) with snippets of dialogue from the film over the intro to most of the songs, so bear in mind that you don't get 'clean' complete versions of each song. Some of the dialogue snippets are funny in their own right, some of them only make sense if you've seen the film but if you buy the soundtrack then you probably have.
If you tapped your feet when you watched Hot Fuzz then you'll want this album.