Google Talk, released yesterday, isn't yet ad-supported - but if it were to become so, marketers are saying they would jump at the opportunity, just as they have with other instant messaging services, writes MediaPost, quoting Carat Interactive media buyer Sarah Fay, whose agency has placed ads on all major IM networks. But whether Google wants display advertising on Google Talk is another matter.

Google Director of Product Management Georges Harik is quoted as saying that Google is not convinced that ads are the way to go for deriving revenue from instant messaging, and says it is looking into ways to profit from the service "in a way that's consistent with the user experience."

"We would be just as likely to use Google as another IM property - if they get themselves to the same level of usage as the others," Carat's Fay is quoted as saying.

AOL's AIM displays banner ads above users' contact lists, including advertising from Classmates.com and Fox. Yahoo uses its messaging tool to drive users to their already monetized properties. And MSN users can download "skins" that brand their contact list and message windows.

MSN Messenger has also monetized video chat via seven-second pre-mercials, offered while users' computers buffer the video connection.