Agreed. I think it's nice to half both. A big review does require competent writings skills because I know for sure that for someone with average writing skils will run out of ways to describe the songs when he does a track by track review. It does take some time to do them as we all know, but they can be worth it if the reviewer is a good one.
Trav is right: It's better to have a small review than no review at all. Provided it's a review that contains more than one sentence (or sentence fragment) in it.