I like the windows open and bright, especially on daytime flights, as I don't really want to be sleepy. Prefer to work. However, on a recent flight back from JFK on the BA178 (daytime flight) I got asked strongly by the lady behind to close my blinds as it was too bright for her IFE! I compromised and closed one, but wasn't impressed - it's not up to her to tell me how to sit in my space. I did look over though and most people, even on a daytime flight, were sleeping or watching a movie with blinds closed. The guy in front of me in 9K was sitting on his laptop though, blinds open, same as me.