While we are working on 5.1 release, some of the fixes seem important enough to be integrated into our 5.0.x branch. The number of fixes seems enough to release an update and we gladly do it today.
The update is recommended but is not mandatory, if you do not experience any issues with your TeamCity setup, you can skip the update.
Thank you all who reported issues and let us investigate and fix them.
Download the new verison and ... happy building!