Northumberland.... they might be more enjoyable too without dp sitting at the other end of the couch watching with me 
I purposefully didn't read the books as generally when a series is 'based on' a series of books it just means they used the names of a few characters and the basic concept so I didn't think there was any great rush... I'm studying like mad atm and the last thing i need is a whole series of books to read 
I'm starting to think they might be worth getting into now though... it never bothers me much when a series/movie and the book diverge plots but it sounds like you guys who've read the books have some background details on a few of the characters that would be worth reading...... and then there's the Eric sex scenes obviously
Plue the prospect of losing Bill Compton by book 4 is very exciting, he's the worst part of the whole series imo