So is there going to be a 4th Eragon book or what?

[Dani is stoked for Nam]

Because i heard that it was meant to be a trilogy but the last one was too big so they split it into 2 books. The first half, Brisingr or something, is already out but the 2nd half isnt. When is the 2nd half going to come out!!!! Jeez its not like hes writing it or anything, its already done!
Does anyone know what going on??

thanks