At £120, the X2 is probably too expensive for all but the most devoted hobbyist photographers -- a normal memory card and cable will probably serve your needs just as well. For professional snappers, however, the X2 is an entirely different proposition. If you're working in a studio, the convenience and security of having your images backed up as you take them will make the X2 a very tempting proposition. Also, if you're a professional on the road, the ad-hoc-network capability will have a similar allure.
Professionals will appreciate the X2's ability to transfer raw image files too. The only downside we can see is that 8GB might not be enough space for a professional photo jockey -- a full day's shooting of high-quality photographs will quickly eat through that storage space.
The Pro X2 may be the most expensive Eye-Fi card to date, but its extra features make it highly appealing. Uploading images over an ad-hoc network, the endless-memory mode and a nippy write speed are all welcome additions. While £120 is probably more than hobbyist photographers will be willing to spend, professional photographers would do well to check out the X2. On the other hand, if Wi-Fi isn't your bag, you'll do fine with just a normal high-capacity memory card.
Edited by Charles Kloet