Although I'm not sure I could bring myself to be as generic as in some of the examples Webb gives, it does make sense to only be specific on things that are genuinely important to you and that you're sure your potential match would agree with. I have a tendency to want to lay out all the potential deal-breakers up front so everybody knows exactly what they're getting into.
For instance, you say you're looking for someone to watch "Curb Your Enthusiasm" with.
Your potential match hates the show so much that he declines to message you.
She says to include just enough information to pique someone's interest, rather than laying out every detail of your personality and preferences.
And keep in mind that the more specific you are, the more chances you give yourself to turn off a potential partner over unimportant details.
I made at least one friend I'm still in touch with today.