Not sure what is going on here, but I did a basic install of WordPress and have the theme "TwentyEleven" running. Install SEO by Yoast. Add a new post and publish it. Take a look at the page source and there is no meta-description or meta-title in the <header> section.
Any clue what could be causing this.
I have 775 perms on everything just for testing, CentOS VPS and newest version of WordPress.