Ah, didn't know that Fosters weren't cancelled.
Ed, Edd n' Eddy had a movie - the Big Picture Show. It was made instead of sixth season. I was hoping for something similiar for Foster's, but as you said, there's still the 10th anniversary to wait for
Don't worry about spoilering - I've seen all the episodes (or at least most of them...) in English. Now I'm trying to watch them all in Polish.