The current channel distributes HTCondor's new features and also incorporates bug fixes.
Most people should use choose this channel and stay up-to-date with HTCondor's latest features.
HTCondor Quick Start Guide (current channel)
In this channel, the second number in the HTCondor version will be odd.
The stable channels distribute only bug fixes to a particular, fixed set of features from the current channel. As a result, each stable channel tends to become more stable over time; read the release notes from the current channel to make sure you aren't missing any features you need.
If you can't regularly upgrade your machines, this may be the channel for you.
Periodically, we will update the set of features that we support with bug fixes and start a new stable channel. This will not the change the set of features available to an existing or automatically-updated installation of a stable channel; you have to make the decision to change manually. However, after a time, we will stop issuing additional bug fixes for older stable channels.
HTCondor Quick Start Guide (10.0)
In this channel, the second number in the HTCondor version will even.