Gadget alert: I use a web site called "Seat Guru" to see how good or bad my airline seats are before I fly. As part of the itinerary I get from my travel agent, I can see what type of plane I'll be flying on, then I can look up my seat and see if it's a "problem seat" or not.
For example, later this week I'm flying to London on United Airlines. I'm waiting for an upgrade to Business Class but since that's never guaranteed, I want to make sure my Coach seat is OK. I fire up SeatGuru.com, select United Airlines from the navigation menu, select the Boeing 777-200 from the list, and I see a seat map of the plane.
SeatGuru color codes the seats. The green ones are the ones you want, the red ones are the ones you don't, the yellow ones are the ones to watch out for. Hover over the seat on the diagram and you'll see a popup that tells you why it's colored that way.
On this next flight, my seat is 22H - not colored at all, so it's a "normal" Economy Plus seat. Tomorrow, I'll call and see if I can get moved to a green one...
Oh - and did I mention SeatGuru is free? Very sweet.