A recent commenter noted that EyeFi simply supports XP and OSX because of the volume on those platforms. It would be silly for them to support the minuscule number of Linux users. Also, most Linux users at least have one XP machine on which to set up the card.
First of all, I kinda hope EyeFi does not release Linux software. We are a small minority and they surely will waste engineering resources on an operating system that they do not understand. I do hope they release information on how the card works. That will let me set it up myself, or let hundreds of others do the same.
Sure, I could go steal my wife's machine to set up the card. But, what do I do when I'm traveling? Isn't that the time I need to change settings in the card the most?