OS X Finder hangs on tagging
6 months or more of this problem... 

my 2013 Mac was hanging when saving files, making outlook 2011 hang often! and slowing down workflows... and after reading this post it dawned on me... 

before Mavericks I used 2 different tagging appx, TAGS and Leap. When installing mavericks, tags were quite well, though they became increasingly slow. 

I I deleted both programs and amazingly and thankfully, For now at least, the hangs in Outlook and find have stopped, it feels like a new Machine. I can only hope its permanent.

Whilst on this topic I had a similar problem with my Mavericks finder a tad's. The centre of the Finder screen used to become transparent and you could not see the files. Drove me insane. Rebooting reinstalling wasting time. I do realise I had an older program called total Finder, Which is really good, installed before I use no bricks. After months of having this problem, then deleting that program, The problem is fixed. 

Moral of the story, if you have installed an app to add functionality and apple then adds the functionality into osx, chances are the app will slow down a your mac. 

Mental motor self and all reading ... uninstall apps of such nature.