The HR44 itself is not wireless and has not WiFi capabilities. This is the most recent information I can find from the Weaknees website.
DIRECTV Wireless Video Bridge for C41W Wireless Genie Mini
The C41W Wireless Genie Client is now shipping. This client requires a DIRECTV Wireless Video Bridge to be connected to the SWM network.
One Wireless Video Bridge can support up to eight Wireless Genie Clients, but only 3 clients can be active simultaneously.
Further, if you need better coverage than one WVB will provide, you can have multiple WVBs on your system. All C41Ws can use any WVB to get access to the related Genie.
The specs for the WVB call for a coverage area of 70 feet and 5 walls. Of course, due to several factors like type of construction and signal interference, we don't yet know how far these will transmit in the real world.
You also need the C41W (not the C41) for each TV. These also incur the same $6/month additional fee just as any additional receiver would. The C41W costs about $100.