The new version is coming in a couple of days. (We're finishing the Mac version right now -- everything else is done).
To tell which version is out view the "Changes in TurboActivate" page. Or on the API page you'll see the version number in the download link. For instance, right now one of the links reads "Download TurboActivate v2.13 for Windows".
We're going to make an opt-in email list for people to be notified when new versions are released. However releasing this new version of TurboActivate has taken priority.