The file on my own website was built following the instructions on the IoT ADT page.
It is the results of following the instructions in the pdf document here and is based on the '140220' (20th February 2014) source package.
I find that the IoT DevKit image is great, and is my standard image now. It has all the devtools built in and you can use opkg to get, install and update hundreds of packages from intel's repository.
It is also fast, it boots and shuts down much faster than some of the other images about. It includes a web server, GCC and G++, debug tools, debug server and so on. It does not run arduino Sketches.
I hope this helps.
-Kenny
