We took the Bering Sea Crab Fisherman Tour while in Ketchikan on May 29, 2009 and we really enjoyed it.
I'll preface my review by saying that I am a water lover, boat lover and a hardcore fisherman in my home state of Louisiana, so my love of this sort of thing may be a little biased.
I watch the Deadliest Catch on Discovery Channel and what takes place on this shore excursion is not as extreme as what you see on that show, although we did haul in 4 different types of fishing/crabbing apparatus.
The entire trip takes place in a beautiful protected inlet 20 minutes or so from the cruise ship dock. The main idea behind this shore excursion is to see and hear about life as a Bering Sea Fisherman. The two main characters on board, Chief and Kiwi, each have been real commercial fisherman for over 20 years. The stories told by these men are the real thing as are the men themselves. You will gain a true appreciation for what it takes to catch many of the types of crabs that Alaskan fisherman fish for.
One unexpected highlight of this shore excursion was seeing bald eagles up close. I do not know if the eagles are always in the area, though, so you may want to inquire if they will be there whenever you will be there. If you are a serious wildlife photographer, be prepared to take hundreds (maybe thousands) of pictures of the eagles.
In my opinion, it was worth the time and money invested.