With relatively little that's obviously new, the final release of Ubuntu 13.10 (Saucy Salamander) seems a somewhat obligatory event. Of course it does feature a new revision of the Linux kernel (version 3.11.0-12) and a new revision of Unity. Also, as with every release, a lot of work has been done improving the various modules that make up the operating system, fixing bugs, eliminating vulnerabilities and improving performance. However, Ubuntu 14.04 LTS, due for release on 17 April next year, will now perhaps come as even more of a shock if its promised big changes are fully realised.
Mir fails to make the cut
Canonical has said that Ubuntu 14.04 and the Unity Next interface, which will support desktop, TV, tablet and smartphone form factors, are dependant on Canonical's new display server, Mir. With this in mind, the Ubuntu developers had hoped to have an early release of Mir running in Ubuntu 13.10 — and indeed it did feature as an option in the beta release, as noted in our Beta 1 preview. Unfortunately, Mir has now been dropped from 13.10 due to technical difficulties and the final release reverts to the X Windows server. Officially this is due to problems with multi-monitor support, but Linux developer Matthew Garrett blogs that, in his opinion, there is rather more to it than that.
rest here