Great story, and I'm surprised to see so little discussion about it (to the point of wondering if there's been another server issue since I checked back last). But what I really want to comment on is Eley's commentary about action in speculative fiction. I definitely agree that action is hugely important in bringing in new readers and giving the rest of us an occasional thrill to stay interested (like many of us, I am sure, I went through several years as a young reader picking up nothing but action SF/Fantasy). But something that went unsaid (though I think it was implied) is a point I've been forced to argue both with with general literary types, many of whom scoff at "paraliterature," and within the genre, and a point which I think was demonstrated by the story at hand: Just because there's action and suspense in a story doesn't mean there isn't more going on. Sparks was definitely a romp, but it also touched on serious issues of the attitudes of "civilized" cultures towards primatives and the role of a hegemonic power in international (or in this case, interplanetary) politics.
On and off since late summer I've been making my way through Phillip Jose Farmer's amazing Riverworld saga, which I somehow missed in my early teenaged years as I devoured the works of Farmer's contemporaries. I have to admit, I myself encounter an over-sophisticated guilt at reading it. But while yes, the books are exciting and action-packed, they also are a fascinating exploration of cultural relativism, an interesting thought experiment in the juxtaposition of peoples from different times and places, and is full of many wonderfully quirky interpretations of historical figures, demonstrating on the part of the author and demanding on the part of the reader an understanding of historical fact and historiography.
When I was a lad, I remember reading Heinlein's Starship Troopers for the first time (and subsequently being horrified at the movie, which came out just months after I read the novel). I admit, I was drawn in by the blowing-up-aliens aspect, but that served as something as an enteric coating for the volumes of political and sociological thought going on in the background -- and while I don't now and didn't then agree terribly much with all or even most of that thought, thinking about it definitely helped me define my own positions on the matter.
Thanks again for keeping these great stories coming.