I discovered that WordPress SEO conflicts with the Social plugin by crowdfavrorite
Social "broadcasts" posts to Facebook and Twitter. The issue happens with the Facebook function. When both plugins are active the title and featured image don't show up when the post arrives on Facebook.
I tracked the issue down to the SEO "force title rewrite" setting. When I turn it off the broadcasts return to normal.
I have no idea why there is conflict but wanted to let people know if you use both.
I did mention to the developer of Social but they couldn't reproduce the issue and the only difference was I had SEO and they didn't.