OK, this is a huge whine but I think it needs to be said...here we go...
We all understand that DL and others have shrunk seat pitch in F over the last decade to a point where it is, well, a little tight for those of us of the taller persuasion, or of the work-on->14 in.-display-laptop-during-flight persuasion. End of the day, no airline is going to increase pitch on domestic F seating, so it comes down to the F traveler to be a little considerate of his fellow F travelers regarding how much recline one takes.
I'm fortunate enough to have a perfect batting record on upgrades for ~40 segments so far this year. And, on about 85% of those segments, the person sitting in front of me has felt the need to be in full recline mode during at least a large portion of the flight -- regardless of time of day. About a year ago, one of the corners of my two-month old Apple PowerBook G4 laptop display (15") got caught by a "rapid recline" of the seat in front of me. The display hinge got tweaked enough so that the display latch doesn't catch without a little torquing during close. Since then, I am hyper about a recurrence.
(Oh yeah, I'm successful about 1-out-of-4 times with a polite request to move the seat slightly forward so I can open the laptop enough to be able to read the bloody screen. And to the guy on the PDX-CVG route today, "may the fleas of a thousand camels infest your shorts."™, usage courtesy of Johnny Carson)
At 6'4" and 220 lbs. (ohmigosh, disclosing personal information) I've never found the need to have a domestic F seat anywhere near full recline -- and that includes 2 years of PDX-ATL redeye (got to meet Shawn Kemp on one of those flights, so shouldn't complain I guess...). I'm looking for folks to treat the seat more like an airline seat and less like their Bark-o-lounger at home. The space behind your seat, like the overhead bins, is defintely "shared".
Comments? Anyone else have this issue?
Oh yeah, they guy in front of Shawn Kemp kept his bloody seat forward for the entire flight...guess being 6'8" and 299

lbs. doesn't hurt in the quest for common courtesy...