Rating: 
 Something in-between four and five stars; for the moment four stars, but might change to five at a later point in time. 
 Review: 
 This book is responsible for something which didn't happen to me in a long time: I was so invested in this story I actually wanted to throw this book at the wall sometimes and even tried to cry at Stephen King to finally let this character die. My reactions were mainly due to the definite division of the cast of characters into black and white ones; "Under the Dome" included nearly no grey characters, but did rather make them either rapists, villains, rowdies and murderers or innocents, likeable, 'normal' people. 
 I love the potential King raises by the initial situation at the very beginning of the novel - the Dome was used to tie different characters to one another, to narrate tragic fates, to weave exciting and thrilling storylines. Neither the beginning nor the ending were especially investing; it was the middle section, the characters' reactions and their behaviors which were so interesting to me as a reader. To be honest, I didn't like the ending very much, but I will delve deeper into this in the part which I marked as a spoiler. 
 My major complaint is how King decided to draw his characters. While some of them like Barbie, Julia, Joe and Rusty were always likeable and in general characters to root for, others like Big Jim, Carter and Junior represented the evil part of the city, and there was no one in-between them. Nearly every other supporting character was either stupid, alcohol-addicted or meth-addicted, and the ones who weren't murderers were characterized as fools. Yet, King established a very wide-colored cast in this novel, and I enjoyed reading about every single one of them. (Well, to be honest, I always caught myself eyerolling when having to read about Andy Sanders, and I always jubilated inwardly as soon as Linda Everett and Brenda Perkins came into action.) 
 For a detailed opinion on the characters and the plot, click the spoiler (which you should only open if you've read the book, since it will spoil nearly everything which could be spoiled about the ending): 
 (view spoiler)[So, the ending was in my opinion a huge disappointment, just as it probably was for many other readers. The identity of the ones who were responsible was pretty much left open to be interpretated, and the actual event itself felt underwhelming and anticlimatic. But most importantly, I would have liked to read more about the characters' reactions to the disappearance of the Dome; what would they be going to do, would they want to rebuild Chester's Mill, would they fear another Dome, how would they mourn their killed neighbours? I've read a suggestion about aliens having built the Dome in order to protect this city from a forthcoming huge natural disaster, an idea I like a lot and would have loved to see being played out. In contrast to many others, however, I didn't particularly mind the way Big Jim was killed. A fight with Barbie or Rusty in the very end would have been too obvious, but I agree that a little confrontation with Colonel Cox might have added some nice aspects to the story. 
 It was suspenseful to see which character was going to die and which would belong to the ones who survived in the very end. At some point in the middle of the book, I started to guess who would die during the course of the story, and I'm proud to say I guessed nearly everyone right. I didn't expect the deaths of Carolyn Surges, Benny Drake and Aidan Appleton, however, and on the other hand, I would have thought Rose Twitchell and Rusty Everett were going to die. The fact that Ollie survived after his parents committed suicide and his brother was killed in an accident was enthralling; I really warmed up to his character during the last scenes. 
 Speaking about the Everetts, it was nice to read about a normal family with two kids and a dog, and I'm glad every one of them (apart from the dog) survived the Dome, mostly because Linda became one of my favorite characters - the scene where she had to deal with Carter was one of my favorite ones. Meanwhile, Junior quickly became a fascinating character, whose fate I was very interested in, but I would have liked a little more complexity in his downfall. His character was very early on reduced to Junior not being himself anymore. 
 King did not only write some really repelling parts (a rape scene should be mentioned here; it unfortunately didn't add anything to the story and did not even see the victim dealing with the consequences), but he also angered me as a reader with the population of Chester's Mill being absolutely stupid and uninspired. The way everyone followed Big Jim reminded me a lot of Animal Farm, a comparison Lennongirl has already mentioned in her review. 
 A secondary observation: Stephen King used an interesting device to build up the atmosphere; every chapter was longer than the previous one in the course of the book [Ch. 1: 4 pages; Ch. 5: 20 pages; Ch. 10: 45 pages; Ch. 15: 59 pages; Ch. 20: 84 pages] before they became shorter again as the ending became closer (Ch. 25: 59 pages). I hope nobody else has already mentioned it because I was really enthusiastic to have figured it out on my own. *grin* (hide spoiler)] 
 Conclusion: 
 "Under the Dome" is a pageturner which I can recommend to every fan of King's books or thriller/dystopia/horror literature in general. It's long-winded, but it also includes many facets of emotional plotlines and characters. It's an epic story I will definitely be thinking a lot about in the near future.