Someone over at
www.androidtablets.net has successfully got an Apple keyboard to work with his TC970. He had to install another utility for it to work, and he reports that is kind of laggy - he types ahead of the input - but that wouldn't bother a non-typist much. I think its a HID keyboard, so the program must convert somehow to SDD. But read it yourself, my perusal was hasty and I might be wrong.
They've started a TC970 forum over there since they were getting so many posts, and that forum might be more useful overall than Mobileread for the 970. I'll continue to post here, though, because I have other devices.
ffred