I hated the ending of My Sister's Keeper. I thought it was a cop out. She opened up this big moral question, and then didn't follow through on it. In general, I don't much like Piccoult's endings.
Sarah Dessen is love. I'll agree with Avery's recs. I think you could start with any of them other than That Summer. (Which I just bought.
I now have all of hers.)
Aaaand, I bought my Spring Awakening tickets today.
ETA: Mandy, I keep meaning to tell you that you should get a Twitter just so you can follow the Glee cast. They're hilarious, and I love them all. My icon is made out of pictures Cory Monteith and Jenna Ushkowitz tweeted of each other.