Just got my Pre this morning. I was able to get my Exchange server properly connected; however, I cannot get it to sync the calendar. Email and contacts sync just fine, but the calendar (one of the key features for me) won't sync.
I've added and removed the account a couple of times. I've also tried to add the Exchange account both from the email app and the calendar app. I've also deleted all other calendar apps (facebook, google, etc.).