Because the previous release was "Tech Demo 1"**. This is "Tech Demo 2" -- I.e., not the full release, just a "demo" of what's in the works. I don't know why it says 3.0
Note also that, if you got a binary package (not something from SVN), you will probably encounter bugs that have already been fixed.
** -- Well, there was the XMas Edition, but that was mostly TD1 + new maps and some rebalancing.