We've just travelled with American for the first time - very impressed with them and would not have a problem doing so again if the price was right.
We flew LHR to Chicago then down to Tampa.
Excellent service, better bum and leg room than BA/Virgin and the food was better, too (they state 'award winning breakfast' - I did enjoy my pancakes and peaches going out since we were on an early flight, DD and DH had a cheese omelette which they said was far better than anything ever served up by VA) and on the return journey I had the pot roast beef and mashed potatoes which was surprisingly edible
We had 2.45hr connection time which was plenty, specially as our flight down to Tampa from Chicago was delayed. We had to wait for the incoming flight - it touched down and 25 mins later we were on board and up in the air

Coming back, because of the time change from Eastern to Central, we had 2 hours which we spent wandering the large amount of shops, trying some food and had a little drinkie.
Their website to book tickets and seats is very easy to navigate and we got the seats we'd booked.
The only slight negative is the entertainment system, which is like the old Virgin Nova system - progs/films all on a loop - and there wasn't a huge choice. But TBH I don't seem to get into the films these days anyway, happy to plug into my iPod, read my book etc.
All in all, I was pleasantly surprised in our dealings with AA
