I disagree with this. For someone being approached a lot, like Arrington, it's obviously easier to give an e-mail a quick glance and then discard it instead of all the time and bother that comes with an almost cold call. But if you want to get through you should call, it's much harder to say no on the phone than it is to discard an e-mail from someone you don't know. You'll also have a much better chance of making an actionable next step. "so you like it? Well why don't I send you a mail with login information so you can give it a try? I'll call you next wednesday to hear how it went"

That's also why response rates on direct mail is much much lower than coldcalling potential customers.