Vaughn walked off X-men. This has the potential to bring Joss back, but it also has the potential to be very, very bad. We should find out who Angel is within the next week, I'm actually somewhat scared because he's very easy to screw up character-wise. I'm also a bit afraid for the casting, obviously, but won't be crying out in pain until official news comes out.
When it does you will know because I may possibly start sobbing uncontrolably.