The problem does not seem to be recognized by Microsoft currently and the Internet is full of places with users who report similar problems. SD Cards with a capacity of 1 Gigabyte are recognized without difficulty. There is no working fix yet for this problem, below is a short selection of forum posts that describe the problem.

Card Reader won’t read 2Gb SD card
Card Reader won’t read 2Gb SD card
SD Card Driver problems
Vista Cannot Read 2GB SD CARD
Vista does not recognize SD cards greater than 1 gig in size

I do not have my notebook with Windows Vista around currently and cannot test if I run into the same difficulties. Let me know if you run Windows Vista and have difficulties with SD Cards with a size greater than 1 Gigabyte.

WiFi is of course what makes this SD card stand out of the crowd. There has been some confusion on how this actually works out and I would like to explain the principle. The SD card can communicate with a computer or the Internet directly and upload pictures taken with the digital camera to those locations. This means that no computer is needed after the initial setup if you want to upload the pictures to sites on the Internet.

Many popular photo sharing and printing websites can be configured using a software that is supplied with the SD card. A USB memory card reader is included with every card which means that you can plug the card into a computer and manage it from there. (Login and password for those websites for instance are stored on the card)

Supported are 40/104/128-bit WEP encryption, WPA-PSK, and WPA2-PSK encryptions and works with Windows XP, Windows Vista and Mac OS X. Only jpg images can be uploaded directly, images saved in other formats are currently not supported by the Eye-Fi SD card.