In terms of coverage the collection is impressive and useful, but it isn't in pretty much any other way. If people want this I'd be glad to make it happen. It's not even all that expensive in terms of disk space since most of the images are fairly small.
Tons of geograph images have already been uploaded to commons. Check the WikiMiniAtlas http://stable.toolserver.org/wma over Great Britain. Their thumbs are displayed smaller to indicate lower picture resolution.
I also recently ran a bot [1] that grabbed location data from the geograph website and completed incomplete image descriptions (adding over 5000 thousand location templates).
Anyhow. I share Greg's feelings on the image quality. Those pics that have been uploaded are there, but I don't think we should drive to upload further stuff from that site, unless it is really needed in our sister projects.
[1] http://commons.wikimedia.org/wiki/Commons:Village_pump/Archive/2008Jul#Oops_...