The Fedora 21 Beta release, originally slated for 28 October, has slipped by one week. It is now targeted for the first week of November.
The decision was made at the last go/no-go meeting, due to several accepted blockers against the beta release. You can see the buglist with proposed and accepted blockers for the beta.
The next go/no-go meeting is scheduled for 30 October at 17:00 UTC in the #fedora-meeting-2 channel on Freenode.
All milestones and tasks are pushed back by one week, including the final release. The schedule is available on the Fedora wiki. If the schedule does not slip farther, the final freeze will be on 25 November, with the final release scheduled for 9 December.