There are several threads about this issue already, both in this subforum and other places at the moment. Sadly there has been no response from staff yet.
http://forum.warmane.com/showthread.php?t=368607
Something definitely needs to be done, though I don't think cross-faction is the first solution for this.
- Enabling some kind of increased XP
(optional and temp of course) for new players could easily be implemented.
- Cross BG's are said to be in the works, but doubt it will come out any time soon.
- Transfers from Outland to Medivh