Lubuntu 12.10 Beta 2 has also been announced by Canonical, on September 27th, after the release of Ubuntu 12.10 Beta 2 (Quantal Quetzal).
There are almost no details on the new Lubuntu 12.10 Beta 2 (Quantal Quetzal), with the exemption of a major bug that got fixed at the last moment.
The installation was completed successfully, but it failed to boot properly afterwards. Lubuntu 12.10 Beta 2 distribution has been fixed and it's available for download.
Lubuntu is based on the Lightweight X11 Desktop Environment (LXDE) and its goal is to provide a lightweight distribution [with all the advantages from the Ubuntu world (repositories, support, etc.)], that anyone can use, no matter how old the PC is.
Download Lubuntu 12.10 Beta 2 right now from Softpedia. Remember that this is a beta release and it should NOT be installed on production machines. It is intended for testing purposes only.