Generally going from the final
RC to the release version should contain as few bug fixes as possible. In an ideal world the final
RC would become the released version without change.
As Steffen has indicated there have been several release blocking bugs fixed (and a couple more still to fix) so it's prudent that a further release candidate is issued.
At the end of the day it's open source so there is no timescales - no shareholders to please, no marketing campaigns to tie in with etc. - so a final release will happen when we agreed that it's ready. In the mean time continue testing and reporting bugs.
-Mark