These are in no particular order and it's actually really hard to choose just a few, because I tend to love most things that I read. I'll give it a try though.
Beautiful Creatures by Kami Garcia & Margaret Stohl
Ballads of Suburbia by Stephenie Kuehnert
The Forest of Hands and Teeth by Carrie Ryan
Jellicoe Road by Melina Marchetta
Shiver by Maggie Stiefvater
Numbers by Rachel Ward
Devil's Kiss by Sarwat Chadda
The Demon King by Cinda Williams Chima
Academy 7 by Anne Osterlund
A couple of these I just read this last week and Rampant would totally be on this list, but I haven't finised it yet. There were so many more books I loved, but these are the stand outs. I think 2010 is going to be an even more excellent year in YA and I for one can't wait!!