From your testing and experience, which colour works better as a headline, dark red or bright red? Any psychological reasons for it?
Depends on the other colors on the page. Bright red would go better with a true blue and yellow. Dark red (maroon or crimson) would look better against gray and navy.
White and yellow are the easiest colors to read against. Most other background colors are best avoided IMO if you want to get your message read. Black is the easiest and least fatiguing to read. This is tested. Red may be a "stopper" in headlines. I like red headlines though and often use them. And blue. I liek the splash of color. Red symbolizes danger. Blue symbolizes safety. Black and white are authoratitive.
In marketing, red actually often carries an authoritative air, as opposed to danger, but that obviously depends on how it's used. Blue tends to portray professionalism and trust. They often combine very effectively on business-oriented sites. If the headline is for something like a sales letter, red can carry an entirely different message - more in line with the "danger" symbolism you mentioned, simply because of how it's commonly used in hyped-up types of copy.
I must agree that it depends on the page and color scheme. I think as a main headline a medium red works nicely, I dont recommend it for use through out the page though. I recently read an article on colors used in websites and what the users thought of them. Red headlines were thought of as eye catching, but too much red was seen as amateurish. I would keep most of it black, its easy and not too busying looking. If its just your main headline go with a medium red. Bright red (like stop sign red) can be hard to read and too dark and it looks off.
I instinctively dislike red on pages that are trying to sell/promote to me. It immediately makes me feel slightly suspicious, slightly cynical and slightly alienated. I prefer any other colour, really, but dark blue and dark green both look good (depending on the background, of course). But even more than that, I intensely dislike Sentences Where Every Word Fatuously Begins With A Completely Gratuitous Capital Letter; this just makes me want to ridicule the site. Lucky for people selling stuff that I'm not a "typical prospect", I suppose.
A good indication of what works from time to time and also to see whis very much in vogue is to check on the colour schemes that Google and Yahoo use. Of all the thing Google might be...stupid / unresearched isn't one of them.