Google says:
qd (or qd) means 'one a day', or 'daily'
(eg. as seen on a prescription)
From the Latin quaque die
But more likely it means something cool. like 'Q-Deck', where the Q means four like it has these four functions: Phone, Games and Music 8)
Edit: sorry, that was just three functions. I just heard from a reliable source that it has a camera too (putting the 4 in Q). In the pictures you've seen there doesn't seem to be any camera lens whatsoever. That's because the battery is also acting as a lens cover. In order to take pictures you must remove the back cover and battery. Double 8) !