I seem to recall from one of the FAQs that they won't support G3s at all.
Well, yeah, but I thought that had to do with the ADB issue, and that's apparently solved now. (Though I dunno, was ATI as free with documentation on the Rage series chipsets as it was with Radeons? That might be an issue.)
Anyway, it'd just be nice - the Lombard is too slow to run OSX pleasantly, but it should handle an Amiga-derived OS perfectly fine, I'd think...