Aisle, and near the front of the plane, for all of the reasons mentioned.
The downside to the aisle is the Drink Cart. I’ve gotten whacked on my elbow a few thousand times.
Fortunately, I have enough miles saved up to get an upgrade most times.
-Cem
Window, near the back unless I have a tight gate connection to make. I enjoy looking at the scenery unfold below me and I like to spot landmarks when I can. I like the back because I can get on first and then when the plane gets there I just chill for 10 minutes while all the people in front of me get all their crap out of the overheads. I try very hard not to drink much before flying so I don’t have to go to the bathroom in flight.
I prefer an exit row seat on the aisle, unless I am flying business or first class. Then it really doesn’t much matter and I tend to prefer windows because it’s easier to sleep.
For shorter flights I sort of prefer window seats, especially flying in and out of Tampa, since there are all sorts of interesting, to me, sights to see. I prefer the left hand side of the plane, because you generally get a view of the bay and bridges, and sometimes I can spot my house.
Window seat whenever possible. I like to look out, both on takeoff and landing, and during flight (assuming you can see something other than clouds).
Window seat.
Even though I usually seem to get a view primarily of the wing. I loved the plane I flew on recently which had propellers on the wing which sat up above the window–great view.
But I like the idea of being able to look out, and I’d rather climb over people than be climbed over (and I can’t remember the last time I needed the restroom on the airplane–transatlantic flights excepted).
I used to prefer window seats. Lately, the extra room the aisle offers has made me switch my preference.
The last time I booked a flight face to face, I requested aisle, then added, “And I’d prefer nonsmoking as well”.
Window seat for me. I am afraid of heights, but this doesn’t seem to trigger when I’m on a plane; I love looking out the window, and do it frequently to rest my eyes, as I always read books on flights.
Short flights I am pretty much indifferent, since I don’t plan on getting up at all, but on longer flights it has to be the aisle.
I’ve read that fear of heights does not kick in unless you’re still attached to the earth in some way. On a roof, on a cliff, etc.
That’s what I’ve been told.
But I’m still not going skydiving, ever.
Window window window! It feels more “private”, it sometimes gives you something to lean on, and nobody has to squeeze past you. I hate being surrounded by people at the best of times - being surrounded them thisclose is pretty awful, and if I can do without one of them, that’s great. Also, I hate having the aisle and falling asleep and getting hit in the head with the drink cart. That sucks.
A big, huge, ME TOO to this. I prefer any seat to an aisle seat, even the middle seat! I like to cross my legs, and every time I’m in an aisle seat with my legs crossed, I get kicked, knocked or bumped, by people or carts or whatever. My elbow gets bumped and knocked on the armrest. Ugh, I HATE the aisle seat. It feels WAY more constricting than the window seat to me. HATE.
Window, both to see out and to lean against when I try to go to sleep. And no one needs to climb over you to get out.
My wife, who is a bit claustrophobic, needs aisle seats, so we’re compatible when we travel together.
Not that I mind an aisle seat. I do mind a middle one. The worse middle seat on any airplane was on an L1011, right in the middle of the middle set of seats, near the back of the plane, where the seats go from 5 to 4. The middle seat here has the legs right in front of you, so you can’t even put your feet out. Should be reserved for people under five feet, which I’m not.
I can only take the window seat if I don’t drink any soda or beer during the flight, and I’m not about to go without at least one of the two. So aisle it is. On a <1 hour flight, maybe I’ll take the window, but otherwise I like not having to monitor my liquid intake.
I actually don’t mind the middle too much, because it means that I have one less person to crawl over to go to the toilet. And you can still see out the window if you’re in the middle, most window people will share around take-off and landing.
I’m small so I don’t care much where I sit. I like to switch with a big guy if I’m on the aisle…so they don’t have to be as disruptive (or embarrassed) when they have to get up.
I’ll call you the next time I’ve got to fly, so long as you don’t mind meeting me in LA first. 
Aisle. Unless it’s a very short flight, I’m going to get up at least once–on a long flight, several times–and I hate climbing over people to get out.
I feel slightly sorry for people who fly so much that they don’t get a thrill from the view from a window seat. As for people who don’t fly much but still don’t demand a window seat, I just cannot understand them. How often do you get a chance to view the Earth from 40,000 feet? OK, much of the time you are looking at clouds or indistinct haze… but some of the most thrilling sights I have seen have been out of a plane window. The Seine winding through Paris on a very clear day. A large and recognisable section of the English coast, and that of France, all in the same view. Coming in to land at Heathrow from the east is always good sightseeing.
I like the window, but lately, it seems I end up on the aisle more often than not. I don’t sleep, and I rarely need the lav, so those aren’t issues for me. I like to watch the world move by, trying to figure out exactly where we are by landmarks and roads and rivers.
On the other hand, when on the aisle, it’s easier to manipulate my carry-ons. I prefer having my tote under the seat, and I can access it more readily if I’m on the aisle. Plus I get to stand sooner, and sometimes that does make a difference.
All in all, tho, I prefer to avoid flying. It used to be fun. Now it’s a pain in the butt. Or I’ve become an old grouch. Either way…
Window, and the closer to the front the better; gotta see out, don’t care what time of day or weather conditions. I don’t complain too much if only an aisle is available. I absolutely hate middle seats, however.
My personal favorites are the Embraer regional jets with a single seat on the left side. I get a window AND an aisle. Whee!