Something to think about...
USB is a Host to Device bus only... each device can't talk to another device.. it simplifies the devices in a structure like this. To add Ethernet or Wifi to Phidgets, you would have to integrate it into each phidget or some sort of custom interface. Having each Phidget device have its own TCP/IP stack (capability) in itself (not counting the Ethernet/Wifi chips) would add significant cost, power requirment, and size to each phidget.
For remote deployments, you might want to consider building a small computer that would be deployed at the location, with the phidgets devices included. For example, an <a href="http://www.mini-itx.com/">ITX based system</a> or an <a href="http://www.advantech.com">advantech Single board computer system</a> would be excellant choices. You could run complex firewalls on it, calculate advanced analasys of the inputs, and your system would be far more redundant with multiple hosts doing processing. On a centralized system, if your 1 machine has a problem, all sensors are down. On a distributed, a limited number are affected.
Anyway... thats my take on it. I would much rather buy the small $75 8/8/8 module as is, rather than an expensive $400+ module with ethernet or wifi.