I always try to get the window seat... and have the wonderful opportunity to watch the world go by outside. When I do have the window seat I feel an overwhelming obligation to look out the window and not waste it. On those occasions when I've been stuck in a middle or aisle seat, I feel really resentful of those who waste the window, watching the IFE or reading or talking, while I'm stuck in the guts of the plane craning my neck to see the fleeting glimpses of scenery around the inert heads and corpulent frames of those who are indifferent to the spectacle passing by (not referring to any of the previous posters here, of course).
I enjoy flying over Hawaii - usually at night on the way to YVR or LAX, so I have to check out the window constantly (regularly referring to the moving map display), in case I miss it (at least I don't annoy the light sensitive with the open shade at night).
I especially enjoy flying over coastlines, watching boats, villages, lights... whatever's on offer (Can't see any of that with the window shade down).
Cities and towns are also worth a look - day or night. I really love flying over sand dunes when passing over western Qld, SA, NT and WA on the way to Europe or Asia. I work in these areas and it looks so much better from the air.
I love flying over mountains - especially over snow-covered mountains - because it means I'll be skiing soon (I'd also miss this with the shade down). I was very sad when we were flying back from Europe a few years back and was made to close the shade when flying over the Himalayas. Apparently some other people wanted to sleep. I tried to hold the blanket up to stop too much light leaking in, but that wasn't good enough for the little Hitler flight attendant.
I always like to peer out the window (day or night) when the plane starts to rock and roll - so I know whether to worry about going through clouds and need to hold onto the armrests to keep the plane up.... or whether it's just Clear Air Turbulence, so it's nothing to worry about and no need to hold on.
IFE rarely can compete with the view.... but of course, if there's nothing at all to see out the window (which is pretty rare), or if I'm sleeping comfortably in J, I'll have the shade down... I'm not an idiot. Well maybe just a little, as it will be lifted regularly to see if I'm missing anything.
Apologies in advance if my open shade bothers you.