Try SmrtGuard SmrtGuard :: Your Smartphone Guardian™ it does an OTA backup of all your PIM information. It is currently in Beta but it is a very good aplication. It also let you pin point the location of your BB and even do a remote wipe if stolen or lost.
I user the Gmail option, I have an msn.com account, but maintain a gmail address just to use the sync. Just remember that if you have it setup for auto-syncing and delete a contact, it will update the online list, so it's a good idea to periodically connect to a pc, I try to do it once a week.
Long Island, NY
VZW BB 8330