By now Ubuntu Linux users are well aware of all the Ubuntu 13.10 changes for the six-month update to the popular Linux distribution as it's been talked about in dozens of Phoronix articles. Today also marks the first official release of Ubuntu Touch for phones and tablets, which is running on Mir, where as the Ubuntu 13.10 desktop is Mir-less by default.
Aside from new features to Ubuntu 13.10, the upgrade is largely worthwhile particularly for new hardware owners due to new upstream packages of the Linux kernel, Mesa, GCC, etc to make for much better performance. On recent systems -- especially if using open-source graphics drivers -- there should be large performance boosts as covered in many Phoronix articles with benchmarks while more test results are on the way. And yes, there will be Linux vs. Windows 8.1 benchmarks.
Those wanting to download the official release images of Ubuntu 13.10 for the desktop can find them at Ubuntu.com. The official Ubuntu 13.10 release announcement is still forthcoming.