Some more beta release are planed to be released in winter. The stable release follows 2015.
Then there will be versions for other languages and a 32 bit versions for older computers or some netbooks, too.
Until then version beta 8 is the most stable version.
InvestiGateIX Beta 8
64 bit version: investigateix-14.11.28-amd64.iso (878 MB)
The complete source code of all running parts is available inside the live-system and the installed system.
After the release you will find a small archive including the Debian live configs and Investigateix sources here and on git.
Additionally the source code of the search engine is available on the Open Semantic Search project site.