I did dither over whether or not to read Inkspell as I found Inkheart a little slow in places but decided to go for it as I can't leave a trilogy hanging......
I'm glad I did, because it's worth the read. As interesting a concept as Inkheart was (reading characters 'out' of books), Inkspell held my attention and imagination better, perhaps because it's more interesting to see what goes on when you read yourself 'into' an imaginary world?
I don't know if it's intentional, but this book seemed to follow the same formula as the first, as far as 'pace' goes. The first third of the book had me turning pages to see what surprises the new world held....the middle third seemed to drop a gear and meander along until it reached the third and final section where the action picked up again. The story is still worth the time spent to read it, but that slow middle bit just knocks a star off for me.
I find myself not liking some characters that I liked in the first book(Fenoglio) and situations (for some reason Farid and Meggie really jar with me as a couple. I don't know why, but they just do), but to even things out though, I found I really missed Elinor (whom I didn't have a lot of time for in the last one) and I'm hoping she gets to join them in part 3..... Swings and roundabouts.
I'm looking forward to the final part, and recommend reading them in order to anyone starting out as they do follow on from one another.