Back in March, I downloaded some free Kindle books to my iPod Touch. These were recent books being promoted by their publisher. One was His Majesty's Dragon by Naomi Novik. It didn't look like my kind of book, but it was free at the time and took 10 seconds to download (I like various SF genres but usually not fantasy). Once I started reading it, I was hooked. On one level it's an alternate history novel of the Napoleonic Wars period, in a world where dragons really exist and have been turned into platforms for aerial warfare with human crews, analogous to sailing ships. These dragons are very smart, sentient creatures with distinct personalities and voices (yes, they talk). They bond very closely with their captains (as the commanders of British dragons are called), and the relationship between the dragon Temeraire and Captain Will Laurence is as central to the story as the aerial and naval battle scenes.
Now I'm nearly finished with the second book (not free, so mission accomplished, marketing people). In Throne of Jade, Temeraire discovers his Chinese roots. The characters, relationships and battle scenes are still good, and you also have the clash of two strong cultures circa 1806 (Imperial Britain and Imperial China). As I've been reading this, I realized that this is really more of a "hard SF" book than a fantasy. Despite the fact that dragons figure in a lot of fantasy books, their role here is more as a somewhat alien intelligence (a second race of sentient beings that has evolved on Earth and has been integrated in various ways into human culture) and as a high-tech "military vehicle." They are definitely not "pets," and the different ways in which Europeans and Chinese treat dragons is a major conflict in the story.
"Hard SF" implies the creation of a world in which the laws of physics, biology, chemistry, etc. are followed quite strictly, though various alternate assumptions and phenomena are added to the mix. These might be aliens from space, devices for faster than light communication or travel, advanced AI systems - or talking dragons. Novik has created a quite believable alternate world circa 1806 that happens to have talking dragons, and it works for me as a sort of alternate-history hard SF. Of course it helps that she has also created good characters and a screen-flicking story line!