Are code reviews worth it?

JamaicaBay writes: I'm a development manager, and yesterday my boss and I got into an argument over whether it's worth doing code reviews. In my shop we've done both a code review or two, and a few design reviews. They are all programmer-led. What we've found is that code reviews take forever and tend to reveal less than good UI-level testing would. The payback on design reviews is meanwhile tremendous. Our code is intended for desktop, non-critical use, so I asked my boss to consider whether it was worth spending so much time on examining built code, given our experience not getting much out of it. I'm wondering whether the Slashdot crowd's experience has been similar?