Moviehole.net breaks the story:
"Remember those rumours a couple of weeks back about Neve Campbell doing "Scream 4"?
Apparently the one-time rising queen of scream was in talks with the Weinstein co. to give her lungs another work-out for a third sequel? She may have had the talks, but she won't be returning, we can confirm today. Nope, Sidney's done with masked men.
Don't despair though. Just because Campbell won't be back doesn't doesn't mean that two of her hot-water bottle sharing co-stars won't be back, namely, the Arquettes. Gail and Dewey vs Ghostface......Let's get ready to rumble?"
The good news is that Wes Craven will NOT be involved. Maybe direct-to-video?