It definitely seems like some of the best official accessories for the Nexus 7 have been taking their sweet time coming to market. One of the best examples of this is the Asus Nexus 7 Desktop POGO Dock. This device has been teased many times, and although this time may be no exception, it appears it might finally get launched very soon in the United States by B&H. The device just went up for pre-order for $39.99 on the B&H website. They even have a tentative ship date of December 30th.
Here's a link below if you want to preorder yours.
Source: B&H - Asus Nexus 7 Desktop POGO Dock