One more time: From the offficial page!

The bestiary page for World of Warcraft: Wrath of the Lich King has been updated with a new creature from the upcoming expansion. Learn more about one of the new species you'll encounter in Northrend, the jormungar.

The fiercely aggressive jormungar are a marvel of evolution, possessing rows of chisel-like teeth capable of boring through solid rock, as well as muscular, flattened bodies well adapted to rapid underground navigation.

Check out the updated bestiary now!

While the bestiary page may cite "Here there be dragons...", there aren't any there for the time being!  I feel betrayed, so I'll just go re-read the info on upcoming WotLK zone Dragonblight!