I bought this game a couple of days after release, and am the proud owner of a level 55 thief by the name of Cafestyle. Or, at least I was. Today I logged in to see that my thief is now level 25, with what appears to be the gear i had at that level. I have also lost all map exploration progress.
I really have no clue why this happened, maybe a bug with the backrolling system, (if there even is one) and I am rather annoyed, maybe someone from the ArenaNet team could do something about it?