Whether you call them "talking heads", "avatars," or "virtual hosts" (or vHosts), banners and sites containing cartooned-heads that can to interact with visitors, are the hot new creative in rich media advertising.

As Judy Gern of agency Carat Interactive says, "The ability to create a character, have it talk to you, and personalize what it says … it's something we couldn't pass up testing." Adi Sideman of Oddcast, one of the tech companies making talking heads possible, explains, "People are drawn to people, even if its virtual. Human faces attract the most attention."

That's the theory anyway. But do they work? Do talking heads annoy Web surfers, or do they get more clicks? And, are the clicks worth anything in terms of conversions? We interviewed the teams behind two recent campaigns to get creative tips and data for you.

Dean Harris, VP Marketing Vonage, is a heavy Internet advertiser who's tested just about every ad format out there, from plain text to rich media, to get more folks to sign up for Internet phone service. Working with Carat Interactive, he tested a banner containing a talking head character, powered by Oddcast, in a national campaign that appeared on Yahoo last fall.

Mark McNeil, General Manager of Sun Pontiac GMC in Mesa Arizona has had a Web site for about seven years. He tested the talking head character "Abby" powered by Eidoserve in a local campaign that launched last fall. His goal was to drive visitors to his site who'd convert to either buying cars or scheduling service.