Kernel 3.7 came out with multi-platform ARM architecture support, 64-bit ARM support, Intel SMAP, btrfs update, experimental SMBv2 support and lots more.
Multi-platform ARM support means a single ARM kernel image can boot on multiple ARM hardware. This makes it easier to support multiple ARM-based hardware for distros. Considering Ubuntu's ARM efforts this is a boon to them, I'm sure.
And with the addition of 64-bit ARM support, that just makes things even better.
Windows has used SMBv2 since Windows Vista. The newly enabled SMBv2 protocol support will allow support of newer features not available in the older protocol. Good for interoperability.
KernelNewbies has further details. Read more.
On a side note, it seems one of kernel 3.8's top "feature" will the the removal of support for the old Intel 386 processor. Even GCC is discussing removing support.
With a codebase that's constantly growing, I'm sure removing some cruft is much appreciated. Hopefully, this also means an opportunity for further optimisations? One can dream...