http://www.seatguru.com/ I just found this site when I was trying to compare AA's S80 legroom to JetBlue's "basic" (not their new plan of having people pay for the exit row), and it seems really cool. It gives tips for where the smaller seats (or larger) are on the plane, and where power ports are in coach, etc. Really nice!
Yeah, seatguru is awesome I love it. I recommend it to anyone who is flying. http://www.sleepinginairports.net/ This site gives you advice on how to sleep in an airport when there is not enough time to justify a hotel room so you just kick back in the airport it also gives advice on how to avoid security and such.
Seat Guru is a great site. I used it when I went to Yellowstone to find the best seats. The only thing they didn't mention that on United flights the aisle row has about 3"-4" less width for under seat storage. There is a bar under the aisle seats to keep luggage from getting caught in the food cart wheels.
AA's S80s have added the same thing. There is basically no underseat storage for the aisle seat on those now.