Found at linux-kernel-stable mailing list. Canonical wants to give back to floss comunity and release an update:
As of Linux-3.5 is the latest stable kernel for nearly all archs, Gentoo should consider to follow closely on this.
Announced as released yet:
It is a pity not to have it at kernel.org :(
Right now, we going to continue to support 3.0 3.2 3.4 3.7 and 3.8 as well as time allows. We are two guys and this is more than a full plate.