Have you ever heard/seen Karl Orrf's Carmina Burana? It's an opera of sorts, the performance of a set of medieval poems to music. It is likely that you're at least familiar with its opening number, the catchy Oh Fortuna!. Well, having seen Carmina, I can tell you that even Orff knew there wasn't much to the rest of the piece – as evidenced by the fact that Oh Fortuna! gets performed twice, once at the beginning and once at the end. You can snooze through the rest.
This month's Fantasy and Science Fiction is like Carmina: a tremendous beginning followed by a largely snoozeworthy remainder. I suppose that, if you want to complete the analogy, you can simply read the opening piece again after finishing the book. You probably will.
(see the rest at Galactic Journey!)