If you actually click on the talk icon and talk to your familiar, you can tell it to go into your backpack. This will tell you all the stats of the familiar as well. The bards get a ferret (with thief skills) familiar and the mages get a fairy dragon. It's pretty cool, actually, though I don't know if the familiar ever has anything to say.

No big secret, but the type of familiar you get is entirely dependant upon your alignment. Good aligned characters get miniature dragons, evil aligned characters get miniature demons, and neutral aligned characters get house pets. Familiars can be fairly useful, although I think they still have a few bugs attached to them. The evil familiars are hilarious - you get the option to smack them upside the head as well as petting them.