Yahoo Inc and Microsoft Corp said on Wednesday they have begun a limited public test to allow users of the companies' respective instant messaging programs to trade messages with one another.
The agreement to work together, first announced last October, marks a long-awaited breakthrough among major instant messaging services, which include AOL's pioneering AIM service, Microsoft and Yahoo, along with more recent upstarts including eBay Inc.'s Skype and Google's Google Talk.
Specifically, users of an upgraded version of MSN Messenger, recently rebranded "Windows Live," can trade messages with Yahoo Messenger, creating the world's largest instant messaging community, with 350 million accounts.
These instant messaging, or IM, systems allow users to type messages to others on their "buddy list" via computers and in some cases over mobile phones. Historically, each provider sought to create "walled gardens" that prevented users of one IM system from talking to users of rival systems.
AOL agreed in December to make its US-market-leading AIM eventually work with, or to use the technical terminology, "interoperate," with Google Talk, but no date has been set to do so. AIM users can already chat with users of Apple Computer Inc's iChat system for Macintosh computers. Google and AIM work with various other independent IM projects too.
With the Yahoo and Windows deal, icons will allows users to distinguish which program their IM contacts are using.
Executives said the two companies were initially testing how to allow their vast audience bases to trade text messages. IM users eventually will be allowed to make voice calls between the two systems, but no specific timeline has been set.
"We are taking the crawl, walk, run approach," Blake Irving, corporate vice president, Windows Live Platform, said in a phone interview. "(Voice) is the feature that we both think is extremely important" to add eventually, he said.
Yahoo and Microsoft said they plan to make interoperability between their services broadly available in the coming months.
It is available in Argentina, Australia, Brazil, Canada (English and French), China, France, Germany, Hong Kong, India, Italy, Korea, Mexico, Netherlands, Singapore, Spain, Taiwan, Turkey, Britain and the United States (English and Spanish).
Jupiter analyst Michael Gartenberg said the Microsoft-Yahoo tie-up marks the culmination of years of jockeying for market share by IM providers. "We have had people say they are working on interoperability for the better part of a decade," he said.
"Consumers have pretty much settled in and defined their preferred IM systems and buddy lists," he said. "It does make it easier for many consumers who will need to keep one less instant messaging system up and running now."
US Internet traffic measurement firm Nielsen//NetRatings data shows AIM with 47.2 million users in June, compared with 28.0 million MSN/Windows Live users and 22.5 million Yahoo Messenger users. The unduplicated audience of Microsoft and Yahoo was 43.5 million US users, the survey showed.
Yahoo and Microsoft took issue with these numbers, citing comScore Networks's global figures which showed that Microsoft IM had 204 million users and Yahoo IM had 78 million users worldwide. AIM had 34 million users, the comScore data showed.