Several hours after 7.1-PRERELEASE name had been created within 7-STABLE, not branched!, 6.4 had also been named for the time being from 6-STABLE. That means that that branch will also soon split into 6.4-RELEASE (the final branch) to continue for the release. As well as for 7.1.. NO PANIC! It will all be over soon, and you can use a brand new release :-)