I use W3 Total Cache for all my of my website caching needs and usually it works great. There have been a few problems with the latest release, but that is for another post.
If I scrolled down to the bottom of the source, where W3 Total Cache inserts its cache statistics, I saw something like this:
Minified using disk: basic (DONOTMINIFY constant is defined) Page Caching using disk: enhanced (Cookie is rejected) Database Caching using apc (Cookie is rejected) Object Caching 1293/1305 objects using apc
The DONOTMINIFY statement jumped out at me. After doing some quick research, I discovered this forum topic, which detailed that the problem is actually in my Wordpress SEO plugin, made by Yoast. More specifically, the "
So, in summary, if you see the DONOTMINIFY notification in your source code, and you have the Wordpress SEO plugin from Yoast, make sure that the anonymous tracking option is turned off.