on AA at least most daytime trancons the cabin is black. People always have their shades down and you are frowned upon if you decide you want to look out the window. I'm not saying it's right or wrong, I just saying what my recent experiences have been (I like the window open).

On a similar note, I'm flying on AA 78 to LHR monday departing at 7. I purposely booked a flight in 4J so the fuselage will block the setting sun to my west and I get a great view outside as the sun sets.