I just had a paper accepted by the Journal of Archaeological Method and Theory, and I want to mention the very insightful and helpful reviews of my paper. We all have horror stories of clueless reviewers: reviewers who are uniformed about the topic at hand, those who have a theoretical or other axe to grind and take it out on hapless authors, reviewers more interested in showing off their erudition than in addressing the paper, etc. etc. But all five of the reviews for this paper were useful and insightful. Several were quite long, with detailed discussions of ways to improve the paper, complete with bibliographies. I stick my neck out on a potentially polarizing theoretical issue. Most of the reviewers were in substantial agreement with my stand, but one took the opposite position. The latter reviewer, however, made some reasoned arguments and useful suggestions without getting bogged down in posturing or trying to prove a point.
Reviewing manuscripts for journals takes a lot of time and effort. Although one is often tempted to turn down reviews when one is busy, active scholars should be reviewing lots of manuscripts for journals. I saw a quantitative analysis once (I think it was in the journal Nature) concluding that an active researcher should review each year six times the number of papers he or she publishes. If one assumes that each manuscript gets reviewed by three people, and that the overall acceptance rate in a field is 50%, then every published journal article requires six reviews. After reading that study I have found it harder to turn down requests to review for journals.
So hats off to Catherine Cameron and James Skibo, Co-Editors of JAMT. They found good reviewers, who wrote excellent reviews -- excellent meaning insightful and helpful, not laudatory. And hats off to the anonymous reviewers also.