No, I don't, but does it make you sad that we all have wait so long for the next one? It takes a long time to write a good book, especilly a really thick one, like Eragon, Eldest and
Brisngr. Ummmm, possibly, ummmm, somewhere in 2010. Or late 2009 if he writes fast.

there has been no official release date yet but there was 3yrs between the publications of eldest & brisingr so maybe 2011? however as brisingr & book IV were originally going to be one book hes probably got most of the story down so it could be mid-late 2010, but i dont think any earlier.

It's called Inheritance it will be realesed in November 2011.