Under The Dome was the only King book that I couldn't finish. If the series is going to deviate from the book like mentioned, I may go ahead and watch this.
As for It, I caught the mini-series the other day and decided to reread the book for the first time since the early '90's. I'm about 100 pages from the end. It's insane how good this book is though I remember the ending being a let down.
The best ending of a King novel since the early days was in 11/22/63, which is funny because King says in the end notes that his son Joe Hill suggested the ending and he changed it to Hill's recommendation. Maybe Hill should do that for every King novel from here on out.