On August 1, 2010 Linus officially released the 2.6.35 kernel.
This kernel is now available in the git repository of Ubuntu 10.04 and you are able to compile your own 2.6.35 kernel for Ubuntu 10.04.
This kernel is backported from the Maverick kernel repository. Kernel Newbies has a nice overview of the new features in the 2.6.35 kernel.
Their summary: Linux 2.6.35 includes support for transparent spreading of incoming network load across CPUs, Direct-IO support for Btrfs, an new experimental journal mode for XFS, the KDB debugger UI based on top of KGDB, improvements to ‘perf’, H.264 and VC1 video acceleration in Intel G45+ chips, support for the future Intel Cougarpoint graphic chip, power management for AMD Radeon chips, a memory defragmentation mechanism, support for the Tunneling Protocol version 3 (RFC 3931), support for multiple multicast route tables, support for the CAIF protocol used by ST-Ericsson products, support for the ACPI Platform Error Interface, and many new drivers and small improvements.
If you’re interested in more details read this article
The Ubuntu kernel developers tagged the 2.6.35 kernel as Ubuntu-lts-2.6.35-14.19 in their repository.
For a step by step article to to compiling the 2.6.35 kernel follow this how to compile article.