We are about to give a class on code reviews to a bunch of the devs on the Avalon team. Code reviews are one of those things that can only help a project. Today we require a code review on every checkin, and in addition have extra tools that validate that each checkin didn't break the build, any suites, or regress perf (still working on getting this one solid <G>)...

Joseph Cooney has some interesting refrences about code reviews...