GrandCentral: Free Net Voice Mail Service

I haven't tried this free web voicemail service...

GrandCentral

However, a number of friends have and say good things about it. One of the interesting features GrandCenral offers is a WebCall Button (free during the beta period) that lets people leave messages for the website's owner without revealing the called number.

Should I place a GrandCentral WebCall Button on this site? Why would anyone want to leave voicemail for a site like this one (not a social network site, etc.)? Let me know what you think.