I'm not discounting the rumor, but at the same time, I'd be very surprised if any of those actors risked being written off of that show.

That being said, the first actor that came to mind was the girl who plays Shannon. I think she has the least amount to do of the entire cast and is the weakest character. Plus, if other rumors are to be believed, she's going to be cast in X-Men 3, which would raise her stock, at least in her mind, and might cause her to go back and ask for more $$$.