I'm reading in a dark-ish room right now. I suspect it may have something to do with the type of monitor used to view the site, because on mine the physical effects are very pronounced.
I feel I can take risks with my blog that I can't take elsewhere. Sorry if it bothers you.
But some people seem to find it more appealing, so I suppose it works both ways.
http://www.456bereastreet.com/archive/200608/light_text_on_d...
For as long as I can remember I have not liked reading large amounts of light text on dark backgrounds. It's always felt as if this was some kind of genetic predisposition for me. While for others, the opposite (i.e. strongly preferring light text on dark background) seems to be true.
I'd be really interested if anyone has heard of some solid research on why certain people prefer one over the other.