Hello Linux Geeksters. As you may know, the final version of Ubuntu 14.04 Trusty Tahr is scheduled for release on the 17th of April 2014. Until then, you can use the Ubuntu 14.04 Final Beta, because it is stable enough for basic usage. (Instructions on how to upgrade from Ubuntu 12.04, Ubuntu 12.10 or Ubuntu 13.10 to Ubuntu 14.04 Final Beta can be found here.)
Ubuntu 14.04 Trusty Tahr will be most likely powered by Kernel 3.13.8, which is the latest iteration of Kernel 3.13. Kernel 3.13.0-21.43 (a version of Kernel 3.13.8 specially optimized by Canonical) has been added recently and Ubuntu 14.04 has already reached the Kernel freeze state, so there are 1% chances that Kernel 3.14 will be implemented on the final version of Ubuntu 14.04 Trusty Tahr.
Due to the fact that Ubuntu 14.04 Trusty Tahr is a LTS version, both the desktop and server versions of Ubuntu 14.04 will be supported for five years, but they will not stick to kernel 3.13 for that long. A new kernel will be implemented on Ubuntu 14.04 with every point release. (the point releases do not bring any new features, only new kernels and bug-fixes).
For those who don’t know yet, Ubuntu 14.04 Trusty Tahr will be coming with a lot if interesting new features, including: a feature for minimizing the windows by single clicking the launcher, locally integrated menus (a feature also present on GNOME 3.12), improved shutdown dialogs, a new feature that allows the users to increase the volume up to 200%, a rewritten Unity 7 with support for window filtering by title, Unity Control Center as a replacement for GNOME Control Center, and of course, a new default wallpaper and 11 other pretty wallpapers submitted and voted by the community. Also, the Login Screen and the Lock Screen have been made to look identical.