The spec and the wiki (http://fedoraproject.org/wiki/Projects/Mock) should also be updated, in case the tarballs have a new home. Off topic: Do the build servers look at the Source: tag in the spec when building the packages? I'm wondering if the next mock build will break if it can't find the upstream sources.
Mock specfile updated to point to https://fedorahosted.org/mock/attachment/wiki/MockTarballs