I flew DL (ok, first mistake) from ATL-LAS a couple of weeks ago and the first thing after takeoff the couple in front of me did was recline their seat back the whole way. I in turn reclined my seat back about 80% -- trying to alleviate the domino effect, but I did need the room.
I know FAs have it tough enough with the idiots that fly these days, I can just imagine a big fight breaking out about these 'gadgets'. I guess it would be flight, a paid dinner, and a show!