BI: Conversion opens new parts of the techtree?

[Duke John]

Here is a quote from the official list of features of BI:

Religion - is now an important factor. Christianity has become the dominant religion of the Empire, but it’s your choice whether or not to revert to paganism in the hope that this will bring victory. Barbarian factions can convert, opening up new parts of the technology tree in the process.

Has this feature made it in the final version? I cannot find any reference to it in the files or manual. Has anyone converted a Barbarian faction and found out that he is now able to build new buildings and which ones?

Cheers,
DJ