To eat fish or not to eat fish?

A debate here:
http://scienceblogs.com/shiftingbaselines/2007/04/a_seafood_debate_to_eat_or_not.php

And various guides:
http://www.audubon.org/campaign/lo/seafood/seafood_wallet.pdf
http://www.mbayaq.org/cr/seafoodwatch.asp
http://www.blueocean.org/Seafood/
http://www.enature.com/articles/detail.asp?storyID=509#Anchor-list2

Alaskan salmon good, US farmed shrimp might be okay, especially from Ocean Boy, imported shrimp bad, tuna depends on variety and how its caught.