The problem is Craig and ED haven't presented much of a unified front on this..
ED has made it pretty clear he wants to run Linux on his, and since he's selling Pandora 2 from his shop I would expect at a minimum that ones purchased from him will have the option of being preloaded with Linux. I can't say for sure that means Angstrom, but I'm not really sure what the fixation is with Angstrom either.. still seems more likely than something else.
ED has also said he'd like a dual boot if possible, but doesn't know yet if there'll be space. To clarify, he said that if it has an internal (micro)SD card for storage it should have room, and if he can technically work this out I'm sure he could at least sell it as an option too. It's feasible that ED would offer an option that Craig wouldn't, but that'd be pretty stingy on his part.
So if you just want a device that's shipped with Linux it's pretty likely you can get one. If you want a device where ALL of them are shipped with Linux that's still up in the air. And it's unknown how "good" the distro will be, at the very least device specific drivers need to be written/ported from Pandora.. notaz did a lot of that work on Pandora, and he isn't very interested in Pandora 2 at this point, so it could be a challenge.