I've got much more to say about this elsewhere, so I'll give you a potted version for now. Franzen has written a novel designed to frustrate the reader at many points so that he can provide an intense pay off. Some characters annoyed me at multiple junctures yet managed to win my affection at the most surprising times and the ending, though perhaps sentimental, provoked unexpected emotion from me.

In short: good book, worth the battles with the characters that occasionally arise. My much more verbose full review can be found here.