I had the dreaded Load app 522 or whatever error that bricked my Tour. I thought all was lost but to my very delighted surprise I had installed Google Sync the week before. It actually prompted me if I wanted to restore my BBM contacts I just said yes and they repopulated my berry. As well as my contacts and calendar! I was thrilled because I had been a bad boy and not backed up my berry for over a month. Not like me but I came out good on this one
I definitely recomend and use google sync. It saved my skin.