Canonical released the first beta of the new Ubuntu 16.10 yakkety Yak αλλά μόνο για τις opt-in γεύσεις, δηλαδή το Ubuntu MATE, Kubuntu, GNOME, Lubuntu, το Ubuntu Studio, and Ubuntu Kylin. It seems that Xubuntu is not present in the first Beta version.
Ubuntu itself is not available as Beta 1, and will only be released as Final Beta, which will be the second and final Beta. 
As you may know, Canonical will try to replace Upstart with the systemd, will consolidate and fix networking configuration through the implementation of the “netplan” project that we will see in the final version of Ubuntu 16.10 Yakkety Yak.
Apart from these, most of the software packages have been updated with the latest versions such as: LibreOffice 5.2 and GCC (GNU Compiler Collection) 6.2.0, as well as the latest firmware version GNOME 3.20 Stack.
The Linux 4.6.7 kernel should come to Ubuntu 16.10 sometime next week, which means it will not be available in Beta 1. However, the final version of Ubuntu 16.10 will be powered by the Linux kernel 4.8, which is currently released as Linux Kernel 4.8 Release Candidate 3.
