Personally, I prefer a more shy partner like the one I have. When you're romantically involved with someone who's shy, getting to know them is like opening a present everyday.
Slamhot Boy and I were driving to dinner and he was in a quiet, shy, but happy mood. He was just gingerly touching my shoulder, and it was really sweet and romantic, and he was talking about music. Out of NOWHERE, he starts singing, "This is It," doing these charicature voices of Michael McDonald and Kenny Loggins. It was electric; I nearly wrecked the car laughing.

Shy people, as you get to know them, have the ability to transcend moods and usually have amazing sensitvity and are multi-faceted and fun to know.