I must confess, I did not read the book, so I cant make any comparison.
But for my taste in this pilot were too many plots to begin with, not one of them made me suspicious... not one built up any tension. What I am really confused of is the weird guy starting to take his girlfriend hostage. it seems he got immediately insane as soon as the dome appeared.
For this and the dome itself I will continue watching it. I think it has great potential! Just hoping for more, than this pilot