We aren't planning to do one. I don't think it's particularly useful to wipe the server of a crowdsourced PvE game. HOWEVER, various parts of your character will definitely get wiped as we revise and rework things. Entire skills have been reset in the past, and probably will again, and I can't promise we won't wipe entire categories of inventory items, etc.
And, well, I guess if a lot of beta testers rally for a character wipe, we can certainly do one... I'm just giving you my current expectation!