This book, an anthology of steampunk short stories, successfully explores the entire subgenre. In that alone it proves its worth beyond other books of its type, but what makes this collection truly impressive is that almost all of the stories are good. My personal favorite was "A Sun in the Attic" by Mary Gentle (fifteen pages that I would have gladly payed full price for) and Neal Stephenson's contribution, though I had all ready read it.
I admit to having been prejudiced against this book when I first picked it up- the stories looked interesting, everything else not so much. The marketing is, in fact, my only complaint about this book. It's a physically huge book, though it doesn't need to be, and the summary is just awful.
That being said, this was one of the best anthologies I have ever read, and I recommend any and all of the stories.