The third beta release in the new Firefox 23.x branch has been made available for download, by Mozilla, for all available platforms.
The binaries for Mozilla Firefox 23.0 Beta 3 can be downloaded and run, without having to install anything.
The Mozilla developers have picked up the pace and they're going through the Beta versions almost on a daily basis.
This latest version introduces a few new features in the toolbox called Network Monitor. According to Mozilla, this is just a classic waterfall timeline view of the network activity.
A detailed list of upcoming features can be found on the official website.
Remember that this is a development version and it should NOT be installed on production machines. It is intended for testing purposes only.