For a technology that enables people the world over to communicate easily, the current instant messaging (IM) networks are surprisingly close-mouthed. Currently, users of the three major IM networks - MSN, Yahoo, and AOL (which Apple uses for iChat) - cannot chat between different services. However, that limitation will start to disappear within the next six months, as Microsoft (MSN) and Yahoo announced last week that they would have interoperable instant-messaging networks by the second quarter of 2006.

<http://www.eweek.com/article2/ 0,1895,1870365,00.asp>

The two networks together represent about 44 percent of users, but eWeek points to research showing that AOL, with 56 percent of the market, has about 40 percent of regular usage. For years, MSN, Yahoo, and AOL have sparred over interoperability, and occasionally one has tried to build a temporary bridge between the networks. But it was clear that only a top-level agreement could pull together the pieces.

Basic shared features between MSN Messenger and Yahoo Messenger will include buddy lists, computer-to-computer voice calling, and emoticons (thank goodness ;-}).

It's possible that this consolidation will eventually force AOL to join the club and allow interconnections as it will be increasingly frustrating for their IM users to not be able to reach the combined Microsoft/Yahoo networks.

In the United States, cell-phone based SMS (short messaging service) text didn't take off until the several cellular operators cleaned up their act to allow simple cross-network messaging. SMS and more advanced multimedia messaging caught on here only after that. Text messaging users in the rest of the world, already able to communicate across networks, were addicted years before.

Windows users who subscribe to multiple instant-messaging networks have had a leg up with the Trillian application for some time. Though Trillian can't bridge different chat networks, it consolidates your login for multiple networks into a single program with additional features. Mac users can look at Fire 1.5 or Adium (in pre-release development). Both support all the major services, including Yahoo, MSN, and AIM, though they don't resolve the issue of a subscriber of one service being able to contact a subscriber of another.

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<http://fire.sourceforge.net/>
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