For those that haven't logged in awhile, from the official forums:
There is going to be a character and claim wipe that will be coming in April.
We’re taking this opportunity to do the *only* character wipe we intend to do. That’s correct; we no longer believe it will be necessary to do a character wipe when we transition from Closed Beta to Open Beta.
All items or bundles purchased on the Marketplace will be re-granted to your new character after the wipe.
We will not delete templates saved in your template window, and they are tied to your account, not your character.
After the coming character and claim wipe next month, there is only one more planned wipe, and that is the claim-only wipe that is necessary when we transition to Open Beta. That’s it; no others.
What is the best way to survive the "wipe" without losing... stuff?
You shouldn’t have to do anything to keep all of the stuff that isn’t being wiped. Any claims you have will be templated up automatically and stored on your account. All templates you’ve saved in your template window are being preserved and will still be available to you after the wipe. Any items you’ve purchased from the Marketplace will be re-granted to you after the wipe, so you’ll have all of that. The only things you will lose are your claim locations in the world, your character, and anything you collected through in-game play, harvesting or crafting.