If you live in the UK, then listen up. The website ukya.com are running a poll looking for the UK's top 10 YA novels. They have been running a top 100 poll, but that has finished. Now you are asked to pick your top 10 from a longlist. There is a huge choice of books to pick from, so you will definitely find a top 10. I'm not sure how long this will be running for, so if you want your opinions to count, you should vote now.
Also check out the rest of the website, as its really interesting, and full of YA news.