I'm pretty shy (except around work...I'm a total goofball with customers), but i do a good job of hiding it....I tend to be drawn to extremely extroverted types because I feel more comfortable in my own skin around them and become more extroverted myself naturally.
I dated a guy once for like 8 months who was not by any definition attractive physically (red hair, big ears, freckles everywhere). We had been really good friends for years and out of the blue he confessed feelings for me, so I gave it a shot. I did legitimately develop feelings for the guy, but then I moved out to Austin. I was young and we both sucked at the long distance thing and things ended up going sour, but it had nothing to do with his looks.
That was a special case though....he is still to this day one of the most gut busting hilarious people i've ever met and I had a strong connection to him before things ever got romatic. Can't see that happening again.