First off I think this is a great project. I'll definitely be buying a board.
I've read around and I realise that R-Pi isn't really aimed at people wanting a hardware platform to hack about on, but I'd be interested in looking at getting something non-linux running (specifically Haiku, but their ARM port isn't particularly advanced). I know the Videocore "firmware" will stay a binary blob, which is fine (as it sounds like that's loaded by the GPU itself before the ARM core is even booted), and that the advanced accelerated multimedia stuff is unlikely to be exposed, but is it plausible I'll be able to set up a 2D framebuffer and write into it without needing any Broadcom binary blobs?
I did Engineering at Cambridge and have a bit of ARM experience, but I'd be mostly poking around in the dark on this one!