With all the problems people are having finding “Compatible” Wireless USB Dongles for their WD’s, I would recommend the following:
Do NOT USE ONE!
If Wired is NOT an option for you, use a Wireless BRIDGE instead.
This is a device that will plug into the Ethernet Port, and then go Wireless from there. The BRIDGE is user-configured to be a “Client” on the wireless network (you configure it separately to work on your network).
The WDTV will be configured using the WIRED Ethernet Port (which is connected to the bridge.)
There’s NO compatibility issues between the WDTV and any bridges, since the bridge is “Transparent.” The WDTV thinks it’s on a wired network, thus no wireless configuration required on the WDTV.
As a bonus, you can position a bridge for best reception a LOT easier than having to move your WDTV.
Examples of Wireless Bridges: (These are NOT recommendations, only used for example.)