The Tauren weapon size has been reverted in the latest internal build and is scheduled to go live next minor patch according to Nethaera.
The original intention of the Tauren weapon size change was to reduce weapon clipping with the ground when sheathed, but it was decided that the end result went beyond what was originally desired. After further review of the change and with feedback from the community as well as the development team, we will be reverting the change to the size of the Tauren weapons when sheathed. We will be making this change in the next upcoming patch and would like to thank the community for all of their constructive discussion on this matter.
Thanks, liquid