I absolutely LOVED this show in the beginning. It had me hooked for the first couple seasons. However, I never really liked Mischa Barton as Marissa. I the beginning I didn't mind her, but eventually I just began to dislike her more and more. I think they could have picked a better actress for the part. I still can't really say what I didn't like about her, but there was something that just got me about her that I didn't like.
I absolutely adored all the other characters, though. But eventually the story-line just went downhill. I couldn't even watch the last season, and I still haven't. I watched maybe like two or three episodes but gave up. This show had SO much potential, but sadly, did not live up to it. However, the first couple seasons were great and I still continue to watch them to this day.