Changelog? The AV has stayed the same, the launcher is now mandatory and with your license you can now install additional junk (radiotracker, speedup etc.).
Ohh.. I won't use Avira again, unless they optimize its resource's usage.
In fact the only stable & performance optimized AV I would use except from Windows 8 Defender, would be Eset. All others I have used, have bugs, or some problem with performance.