I read somewhere that the creators of the EyeFi never really envisioned it being a product that would appeal to professional photographers and since professional photographers' cameras tend to use the CF storage media, they didn't create a version in the form factor.
But, I noticed that the new Nikon D300s has decided to roll out with a dual memory card slots (for RAID1 redundancy or being able to split which card RAW and JPEG go to or to just use as RAID0), but unlike the Canon Mark II, the slots are two different formats (CF and SD). ; So, in theory someone with the Nikon D300s could have this setup mentioned in the article, put the EyeFi into the second slot of their camera and configure it to put the JPG's onto the SD card and let them fly into the cloud.
But, considering the EyeFi card is only 2GB, it better have a configuration option to delete the pictures off the card after upload or one wouldn't get many pictures taken before it filled up