This device is a combination 2Gig SD card and WiFi adapter that turns any camera into a WiFi enabled camera. The scenario mentioned in the articles of sharing photos at a family get together sounds like a great application. However lets think more deeply about it, the scenario presented mentions technical glitches preventing the sharing of the photos on the day. I think throwing more technology at the problem is just as likely to cause technical problems. This is especially true since you can’t change the cards WiFi settings when it is inside a camera. Now if the person hosting the party had a bunch of these cards pre-programmed and tested for their WiFi network then gave them to people to use at the party it would probably work great. But at $100 a piece having a bunch of these things around for a party isn’t economical for most people.
I think a better plan would be to have a PC setup with a multi-format card reader installed. Then be willing to help the party attendees use the card reader to put the photos on the PC for sharing.
Add to this the possibility of a radio transmitter mounted within inches of a sensitive CCD in a camera causing noise in the CCD and the usefulness could be negated. In a few years if camera makers design and test for compatibility with the Eye-Fi this potential problem should go away.