Crafter_Man,
I don’t think that women who ‘like’ jerks are the majority, but they certainly make up more than half the ‘noise’ about what women want/don’t want. As a female and former jerk-o-phile, I have observed much the same thing in BOTH genders… you aren’t wrong, you just didn’t do any stats on it - observation alone produces skewed results. There have probably been plenty of women around you who like nice guys, but they either weren’t looking for a boyfriend, were ‘invisible’ in some way, or they were attached. Many were probably in their rooms, reading books, wondering why the nice guys all went out with bitches who treated them like dirt.
As for women who like jerks and DON’T like nice guys (“too boring”), I can only speak for myself. I had hopelessly entangled ‘excited’ and ‘afraid’ in my emotional lexicon. So when I was with a guy who scared me a bit or treated me in some way that was counter to what was expected (not ‘well’), I got a rush from it. Kind of a good-girl rebellion - I couldn’t be the bad one, but I could sure as heck DATE the bad one! Same thing that makes roller-coasters fun, that fear=excitement thing. It was only when I was with a guy who slowly transformed from ‘bad’ to ‘boring’ that I actually was around ‘boring’ long enough to get used to it. Turned out I really LIKED not being on-edge all the time! I enjoyed being able to explore more than the anxiety of ‘what if today is the day that he _________?’ (fill in the blank - threatens to leave, threatens to kill himself, goes psychotic, assaults me, etc.). Took me a while to really separate fear and thrill, but I did it.
I also had to let go of the rush of being brave, daring, powerful - it doesn’t take a power-house to survive dating nice guys, so being with a jerk can be an ego-trip. Insecurity issue there, too. Half the kick is being able to bitch (a love of flaunting crises is another bad addiction - my mom used to call that the ‘gee ain’t it awful’ syndrome).
After I got over the fear thing, I started dating guys I just LIKED. MUCH nicer. More calm. Less flashy, required I have a stronger ego myself. Also made me a much hotter property - great guys don’t want to always have to hold up a fragile ego, it is EXHAUSTING. Same goes for great girls - I’ve been there, done that, don’t EVER want to do that again.
As for what women/girls want in general, I have to second (etc.) the major votes. Guys who aren’t HUNTING (we can smell desperation a mile off, as can guys), who aren’t afraid to say what they think or feel, guys who have their own lives, guys who are confident about themselves.
The things that have lit my fire the most (in my ego-stable existance) -
A) a guy who has an interest he’s so passionate about that he forgets to try to impress you with it, he just wants to SHARE it because it is so damn cool to him. With my husband, epeepunk, it was fencing (epee being his weapon of choice), and music. He wasn’t trying to prove anything to me, just wanted to share it with me so I could see what was so damn great about it. Funny, it became very easy to be interested in learning.
B) emotional courage/honesty. Epeepunk stole my heart when he calmly and honestly told me that it wasn’t at all funny when I passed out (after an injury on a group trip) - even though I’d made it clear I thought it was hilarious, myself. His tone of voice indicated that it was actually frightening, in the sense that he was scared FOR me. He didn’t think about saying it, he didn’t have to make a statement that was more or less ‘real’ than how he genuinely felt. He didn’t seem to care if I was taken aback by that statement, and wasn’t filtering his choice of words to protect himself later. I can still remember my heart going THUMP!, and that was more than 10 years ago.
C) Competence. Physical competence is a big turn-on. Guys who trust themselves to do a good job on something MOVE well. Physical competence is great, but other kinds of self-confidence are up there, too - knowing you are good at something and can do it well without bragging adds a certain something, and we can smell it the same way we can smell desperation. Doesn’t matter if your skill is cooking, programming, or kung-fu, if you are really hot at it, and you know it enough that you don’t have to show it, it will make you shine anyway. If you are a klutz in one area, see if you can expand your skills in another. Social competance is another fairly hot item, but that alone won’t do it.
Good luck! And as for dancing, I met most of my boyfriends, my ex-fiance, and my husband DANCING (Scottish Country Dance). Just another form of physical competance, but DAMN, men in kilts. YUM! 
: thanks, Dinsdale! Just trying to give some straight dope, even if it is a bit mortifying at times to use myself as the bad example…