I am having the same problem as another poster, the Card Validator says that my pages are missing
twitter:description. Which is true, because when I check the page source, it is missing.
Yesterday's post I manually added the meta tag code to the post content and it started working: http://amiyuy.com/wow/2014/06/alpha-impressions-as-of-june-19-2014/
Today's post is missing it as well: http://amiyuy.com/wow/2014/06/wod-alpha-interface-maps-as-of-june-20-2014/
The only plugin that I have that could even remotely be interfering is Jetpack, and that's simply because I don't know everything it's doing. I do not have any SEO plugins.