My preference is nearly a dark cave and people think I'm odd. I also use a plugin to make FF have dark backgrounds and light text. I don't enjoy squinting all the time.

In at least one case, it wasn't just me. I used to work editing photos on California's central coast and after we moved to a building with loads and loads of skylights, and got a bunch of new glossy-screen iMacs, it was really hard to get color accuracy if you wore anything but a black or white shirt. It was like staring at a mirror all day long. Eventually we got umbrellas to blot out the sun and that helped.