Ok, you knew it was coming!
The website recommends the GHI xbee module to support wifi on the Cerb and Hydra. I picked that up, and the Xbee wifi module (with the wire antenna). I got the OEM part, not the Roving Networks one.
Is there actually a Wifi driver for this? If so, how can I find it? Additionally, any examples of reading data from a URL?