The Oibaf PPA is one of the easiest ways to fetch updated open-source graphics drivers for Ubuntu-based systems (it's only for the user-space drivers, but the Linux kernel can be easily fetched from the Ubuntu kernel archive). The packages offered by Oibaf are newer than what's officially available in a given Ubuntu Linux release and is usually more recent than what's found in xorg-edgers and other Launchpad PPAs.
Oibaf also provides technical assistance and feedback for his graphics driver packages via our forums with this thread.
Anyhow, if you want to easily grab Mesa 10.0-devel for Ubuntu 13.10 without resorting to Git and building from scratch, go check out the Oibaf PPA. There's lots of new features to Mesa 10.0 and will be officially released in November but it won't be found "out of the box" in Ubuntu until the 14.04 LTS release next year.