Michael, thanks for a clear and concise review.
Your findings are well in tune with the prerelease review by Rob Galbraith
For the sake of information, the reason your old card reader and old (well, comparatively) camera hardware don't benefit, is that they don't support the faster UDMA transfer mode that's necessary to take advantage of these cards.
I seem to recall that at least Phase One and Leaf indicated that the new revisions of their digital backs support or will support this UDMA mode.
Canon, Nikon et al have been quiet, as far as I know.
Does anybody else have any reliable
information on support for these faster cards?