D&D in Space, that's what most people say this is, but it's more like D&D Advanced. In the first book, the Starfarer's Handbook, a new set of possibilities are set before gaming groups never before considered. Spelljammer was D&D in Space, using magic instead of technology. Dragonstar presents a universe where all the traditional D&D races have advanced technologically until they reached the stars in starships, not ships reminiscent of old sailing ships.
The Starfarer's Handbook presents everything a group needs to start a campaign, from how races and classes are affected and changed to how magic has changed with the advent of technologies most science fiction fans will recognize. Starships are powered by technology, for the most part, but it requires magical assistance, in the form of the starcaster, a magical item, to move starships from star to star.
Most of the actual setting information comes included in Guide to the Galaxy, which also includes new monsters, spellware, and magical items), but the Starfarer's Handbook does present a history of the Dragon Empire, a starspanning empire ruled by the 10 dragon clans (essentially, all the core dragons from the Monster Manual).
If it weren't for the lack of more "technomagic" in the setting (the starcaster's an interesting and well conceived idea), then this might be deserving of five stars. A worthy setting, it's ashame this isn't more heavily supported.
[4 of 5 Stars!]