Anti-Story is great. A sizable portion (arguably most) of seminal postmodern short story writers are represented here, at a much lower cost than you might expect (I can imagine a comparable Norton anthology running something like forty or fifty dollars). In addition, the editor has organized the stories according to what convention of fiction he thinks they break, and how he thinks they get away with it. In the process, he makes an argument as to what a conventional story is, and how a story that breaks with convention can maintain a reader's interest. This organization, more than anything, makes Anti-Story useful for people interested in how short stories work, and why experimental fiction might be notable or worthwhile. If you teach, the organization could also help you integrate this material into a course, as the book provides such a strong context from which to begin a discussion.
If you like this kind of stuff, you need this book. Buy it.