There are two questions I get asked when introducing myself as a marine biologist at parties: the one about whether I get to play with dolphins, and the one about what kinds of seafood it is alright to eat. Well, I have the answers. They are:
1. No.
2. The Monterey Bay Aquarium has just released a report on the state of the oceans. It is colorful, written for non-experts, and has a photo of a delicious fish taco on page 22. You can download it here [PDF].
If you want the wallet size version, specialized for your region of the country, get it on their Seafood Watch website. You can search for a particular species, or even download an iPhone app.
Now you know.