I've read all the books of the series. I used to like a lot the series when I started it, but now I've got a little bored of it. And there are (many) better series too. But anyway, the fifth book was the best in my opinion, and I hope the movie becomes great too (not like the 4th, which was terrible).
@ Ricky
Will you read it in english or you'll wait for the translation? I think I will wait for the translation, because I'm reading other books right now; but I remember that I had read the 5th book in english