I'm not sure why I am getting this, but I go back and edit a post and a blank tag gets added to the mix. I'm not adding any tags or anything. I don't know yet if it is Safari accidently filling the field blankly or what. Since it is a blank tag it doesn't show up for me to delete. The only way I can delete it is if I go to the Tags area and delete it that way.
I'm working offline, but here is a screencap of the problem.
If you see "projects" there is an extra tag added in there before "newsletter". Again the only way to delete it is to go into the Tags section.
I am going to try and work in Firefox and see if it keeps happening.