It's because he is honest about who he is, as an individual, a father, a husband, an artist, and a geek. He doesn't hide his true character the way that most of us do, and that takes a whole lot of courage and self-esteem. Sure, he keeps some things private, but that's vital to anyone's sanity and totally understandable.
In his latest blog post, Wil talks about what motivates him as a writer. He says,
This is exactly how I feel about my craft, whether it's blogging, reporting, or working behind the scenes in TV. In fact, I was so much in agreement with his perspective that I was compelled to add my own in his comments. I said,
And now you know.