I have just released the Feb 2011 CTP of Gepsio to Codeplex. You can get it here. I added release notes to the page, and I encourage you to check those out as well.
With this release, I have moved away from PDF documentation and into a Wiki-style format which Codeplex supports nicely. You can find the table of contents here. As of this writing, the documentation is slightly out of date, but I will work on it moving forward. The wiki format allows you to see changes as I make them, rather than downloading a separate document.
Enjoy this latest release!