Well, Francine Pascal, the author of the Sweet Valley books has written a new book.
It tells the story of the twins, Elizabeth and Jessica, now in the their twenties, as adults. The full book won't be out till next year but you can sign up here to read the first chapter online.
Yes, I did it. I read a few of the Sweet Valley books in high school, so I was familiar with the (never changing) plot and characters... and I was procrastinating. If you have 10 minutes to fill and remember the books from their/your younger years it may interest you.
Are you going to go catch up with Elizabeth and Jessica?