As widely expected, Google waded into the instant messaging space today with the debut of Google Talk, an Instant Messenging client that also offers the ability to make voice calls between computers.
You have to have a Gmail account to get Google account. You can download Google Talk here
As said, Google’s got a real challenge in weaning people away from existing clients. Just look at the installed user bases of its rivals, from figures comScore sent out yesterday to the media. Figures are the millions of unique visitors each service had in July 2005
AOL AIM (for non-AOL subscribers): 30.9 million
MSN Messenger: 23.3 million
AOL AIM (for AOL members): 23.1 million
Yahoo Messenger: 21.6 million
AOL ICQ: 1.8 million