Has anyone used a JeeNode to connect to the internet? I'm currently using a WiShield which works great, but a JeeNode is much cheaper.

The mentioned "wireless communication" is for communicating between nodes, not WiFi. The moderndevice page says "Radios are available in 915 MHz in the US and 433 & 868 MHz in Europe, all unlicensed utility bands.". WiFi is in the GHz range.

I have a set of jeenodes around the house sending data to a central jeenode communicating with one of my servers though USB - so the radio on the jeenodes is purely to communicate between the jeenodes in a extremely inexpensive manner - and even better the jeenodes use very, very little power can can be run from a set of AA batteries.

So you will still need to communicate with the internet through a separate computer or indeed a Arduinio, but if you have more than one node they are much much less expensive than using Arduinos.

for inexperienced users/programmers, how easy is jee to use for something like, home access control (alarm) and maybe smart thermostat?