It doesn't add nay real new features, beside adding simplified Chinese, but rather expands and fine tunes existing stuff. Weighs in at 1.5GB download.
Motion got fast with opening projects and ingesting images.
Compressor is speeding up MP4 and AVI rendering. It supports now CPUs without monitors in the cluster - build a render farm with a bunch of second hand Minis like you can do in Blender (that's cool!)