Google has a blog entry about it here:
http://googlecode.blogspot.com/2009/10/mercurial-server-side-clone-support-for.html
Once we've kicked the tires on this new feature, we should probably
discontinue the BitBucket mirror.
You can view/create clones of iUI from this page:
http://code.google.com/p/iui/source/clones
I've updated the Contributing and UsingMercurial wiki pages to mention it:
http://code.google.com/p/iui/wiki/Contributing
http://code.google.com/p/iui/wiki/UsingMercurial
I created a public clone and changed one file as a quick test, you can
see it here:
http://code.google.com/r/msgilligan-test/source/list
I don't see any kind of 'submit pull request' feature or any way of
generating a server-side diff between revisions in different
repositories. Hopefully Google will add it in the future. It looks
like merging changes from clones will have to be done on the client side.
-- Sean