There were hopes that the Linux 3.14 kernel would make it into Ubuntu 14.04 LTS given that it has much better Intel Broadwell graphics support, other new hardware enablement, and a ton of new features. Sadly, it looks like only the Linux 3.13 kernel will be shipped by default in Ubuntu 14.04 LTS. Fortunately, with the new hardware enablement strategy of Ubuntu Long Term Support releases, in 14.04.1 or 14.04.2 we will see a new kernel (along with Mesa/X components) back-ported from later release series.
At the Ubuntu Kernel Team Meeting this week the meeting notes reflect that currently they are running on the Linux 3.13.6 upstream stable kernel, the 14.04 freeze is 3 April, and that they're mainly looking for any outstanding patches to be proposed prior to next week. Early on in the Ubuntu 14.04 cycle the Canonical kernel developers acknowledged they would likely end up with a Linux 3.13 franken kernel as opposed to having 3.14 in time.
The Linux 3.14 kernel was expected to be released last weekend but Linus delayed it to this coming weekend. The Linux 3.13 kernel is still a big improvement over Linux 3.11 found in Ubuntu 13.10, but it's too bad that Linux 3.14 isn't making it. Those wishing to install the Linux 3.14 kernel manually on Ubuntu 14.04 or any recent Ubuntu Linux release can rely upon the wonderful Ubuntu Mainline Kernel Archive that also provides daily kernel builds of the latest Linux kernel Git. It's a big time-saver and we rely upon this repository a lot at Phoronix for getting reproducible kernel builds and saving a few minutes from doing our own kernel builds when installing new systems so frequently for Linux hardware benchmarking.