The tenth 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 10 can be downloaded and run without having to install anything.
Mozilla has yet to release the particular changes in this latest version of Firefox, but users will be able to downloaded the official binaries.
A detailed list of upcoming features and other various changes 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.