Everyone's an expert now, but who really is?

With the advent of blogs, Facebook, Twitter, and LinkedIn, it's easier than ever for someone to get "published" and to be an "expert". Case in point - this guy (pointing at myself).

But what really constitutes an expert nowadays?  Is it the guy or gal who creates the most blog posts and distributes it to the most friends and followers on Facebook, Twitter and LinkedIn? The one with the highest Klout score?

Back in the day, you were an expert if your work was included in a respected publication such as the New England Journal of Medicine, the New York Times, The Economist, etc. But now with user-generated content sites such as Huffington Post and Bleacher Report and the aforementioned social networking sites, it seems that everyone now has an expert opinion. I don't mean to break this down into black and white; it's just that I subscribe to many industry blogs and newsletters and have realized that a lot of the content sounds the same.

So have there been so many experts all this time, and now they just have more media to broadcast their expertise? Or do we go back to those respected publications to identify those true, distinguished, proven experts? Or somewhere in the middle?

I really don't know, so let me know what you think!