Hi Craig,
How's the project going? I'm trying to do a similar thing, following along with Felix's Raspberry Pi gateway example. I kinda got stuck with the socket.io. I'm not much of a linux user, basically just copy and pasting what I see with some goggling when I run into trouble.
Is it bad form to ask for SD card images? I'm looking for a RPi + Arduino solution for wireless sensor network, but it's been slow going trying to get the socket.io and all that other webserver stuff going.