I actually received an unsolicited call from a Biznik member who was pushing an event she was hosting outside of Biznik.
I was a little irritated because she made it sound like she was interested in my company at first and then switched into her pitch. Kind of made me do a double take.
I don't know. If you have something that you feel will really interest me, I'd prefer email above anything else. We're all busy solo-pros and when you catch us on the phone trying to sell us something, well, to put it bluntly that's not a good use of our limited time.
The only time I actually pick up a phone and call someone on Biznik is after I've made email contact and have gotten a positive response -- usually the email was sent as a response to a "need" post, so it's not entirely unsolicited.
Or I call a service provider from Biznik because I am interested in their service and not pitching my own. I believe that is courtesy.
If you value your time, you should value other people's time.
Bizniks unite! =D