The new program, Google Talk, will compete against similar free services offered for several years by America Online Inc., Microsoft Corp. and Yahoo Inc. All are vying to increase their presence on PCs to boost online ad revenue and name recognition.
"Right now, AOL is the 800-pound gorilla when it comes to instant messaging. Its AOL Instant Messaging Service is used by millions of people," says CBS News Tech Guru Larry Magid. "When it comes to instant messaging, the size of the market does matter because it only works if your friends or business associates are using the same service you're using. So, Google has an uphill battle to win over users."
AOL's messaging program has about 41.6 million U.S. users, followed by Yahoo Messenger with 19.1 million and MSN Messenger with 14.1 million, according to ComScore Media Metrix's July report.
As for the PC-to-PC chat service, Magid notes "the voice service is very nice but it's not unique. There are already a number of free PC-to-PC voice services."
Click here to listen to CBS News Tech Guru Larry Magid put the new Google Talk service to the test, in this podcast interview.
Wednesday's launch of the instant messaging and voice chat services comes two days after Google unveiled its new , which can scour users PCs for files. It also comes less than a week after the company announced plans to raise $4 billion in a secondary stock offering - which some analysts speculated could be used to fund far-flung projects such as Internet telephony.
Users of the most popular instant messaging services are unlikely to switch unless the friends and colleagues on their "buddy lists" do the same. The different instant messaging services still do not communicate with each other, though promises of such "interoperability" have been made for years.