[austenallred]

I don't know, there are so many factors that go into SEO that assuming, "Oh, it's the hyphen in the domain name" seems a little anecdotal to me.

[bluetidepro]

This was my first thought, as well. Also, with how often search engines re-factor their search algorithms, it makes you wonder if an article from 2011 is still even relevant? Anyone else have some insight maybe on that front (relevancy a few years later)?

[sp332]

I think they did a pretty good job of controlling for all variables other than the hyphen. What else could it be?

[kodablah]

They swapped the content. Maybe the algorithm favors the site with content earliest?