Sometimes I wonder if I'm too nostalgic about these things. I bought my copy at a 6th-grade book fair, but the stories in it keep coming back to me.
Many of them, like Phillip K. Dick's dusty "Second Variety," either never quite strike the right tone, or are a little too short to really shine. The rest of the stories, however, far and a ways make up for it.
Lucius Shepard's 'Salvador' is a fantastic piece of magical realism, although it mostly serves to remind me of his excellent novella, "R&R"
Ian McDonald's "Floating Dogs" is told form one of the most fantastic and eerie points-of-view I've seen across sci-fi.
Dozois' own "A Special Kind of Morning" is one of the most finely crafted works I've seen in the genre. It plays on the humility of the narrator's telling to slowly add flesh to the story, and contrasts the immense devastation of high technology with the horrifically unthinkable methods of war known to our era.
"A Dry, Quiet War" is, to this day, pretty much my favorite story anywhere. Tony Daniel's poetic style leaves spaces the size of endless galaxies free to the imagination, serving as a starry backdrop for one man's very personal trials.
Of all the science fiction I devoured as a child, these are the stories that still come to mind, all on their own. If you haven't read them piece-mail by now, in "Year's Best"s or Asimov's or what have you, then this collection is definitely worth your time.