latest beaglebone kernel?

I haven't updated the kernel for my beaglebone in about 6 months. Is
the beaglebone-3.6 branch the latest version for the 'bone or should I
be using 3.9?

I tried:

# git clone git://github.com/beagleboard/kernel.git -b beaglebone-3.6
# cd kernel
# git checkout origin/beaglebone-3.6 -b beaglebone-3.6

But I get "fatal: A branch named 'beaglebone-3.6' already exists".

BTW, how's it going with mainline?

- Grant