I've been looking into this and the state of hacking the Nook today is awesome. Dual boot between any two of stock, Froyo, CM7 (in progress), and Honeycomb (!) (in progress) from the device itself, plus stick in any SD card with an installed OS to boot that.
When the Xoom (and its source code) officially drops later this week, full Honeycomb on this won't be far.
When the Xoom (and its source code) officially drops later this week, full Honeycomb on this won't be far.