I don't form grudges well (that takes effort and memory, and I'm lazy and like people socially to eat, drink, and be merry) and do worse at keeping them. I think we're all pretty forgiving as a group though. A good example for me is Tenshi: she's one of my favorite posters now, and many know what foot she and I got off on.
There have been psychological studies on who you end up liking best in life. You end up liking, from most to least, in the following order:
(1) Someone who you initially disliked, but grew to like.
(2) Someone who you liked initially, and continued to like.
(3) Someone who you disliked initially, and continued to dislike.
(4) Someone who you liked initially, and grew to dislike.
I guess being pleasantly surprised by people who rub you the wrong way initially is always a good thing.
Regards,
-Flip