Speaking with Entertainment Weekly, Wes Craven divulged a bit more info concerning the plot, which in true Scream fashion is delightfully meta:
"There have been 10 years of no Ghostface, but there has been the movie-within-a-movie Stab. We have fun with the idea of endless sequels, or "sequelitis" as Kevin calls it in the script. Sid goes through these three horrendous things, and Stab was based on those horrible things. And then they've been taken by a studio and run into the ground in a series of sequels. She has been off by herself and living her own life, and she's even written a book that has gotten a lot of critical acclaim. She's kind of put her life back together in the course of these 10 years. But, certainly, there would be no Scream without Ghostface, so she has to confront him again, but now as a woman who has really come out the darkness of her past."
Although I'm ambivalent toward the first film, enjoy the second, and think the third is merely a parody of the other two, I'm genuinely looking forward to see if Craven and Williamson can update the series for a newer generation in a way that plays off what are perceived as the strengths of the first. Also, considering how much I loved the soundtrack to the second one, here's hoping they can do it again.
Head on over to EW to check out the rest of the interview.