Thread:Extension talk:OpenID/CAVEAT: Google's OpenIDs are Unique Per-Domain/reply

Thanks for reporting this issue. I already knew the problem, for example from this report https://drupal.org/node/1223386.

You asked "Is the SVN version able to work with Google's changing OpenIDs?". Answer: no, currently not, but the SVN version allows users with an OpenID account to associate a normal password to the account, which was not possible in older OpenID versions. This can at least help to overcome (wiki) domain move problems.