I finished Eclipse a few days ago. I've heard a few people say they didn't enjoy this book as much as the others, but I still found it pretty good. There were some slow parts, but I felt the book reinforced Jacob's feelings for Bella, and helps us see how she feels about Jacob.
I've started Breaking Dawn (about 300 pages into it), and this one is a little more difficult to grasp for me (As if a world with vampires and werewolves should be easy to grasp in the first place!). I'm also undecided yet on how I feel about the shifting "books" within the book. First we have Bella's viewpoint, now we've shifted to Jacobs...I guess I'll withhold judgement until I finish the book (which shouldn't take long!)