ActiveWin:

"Cerulean Studios, maker of the Trillian IM client, is at the top of Microsoft’s hit list. Trillian enables users to consolidate multiple IM accounts in one client and is available in a free version, as well as a $25 Pro version that offers additional features. Trillian has been downloaded more than 10 million times, according to Cerulean Studios. "Running an [IM] network is expensive," says Lisa Gurry, group product manager for MSN at Microsoft. "We can’t sustain multiple other-people’s businesses, particularly if they charge for certain versions of their software. We’re introducing licensing processes for third parties like Trillian.""

A few years ago, MSN tried for months to interop with AIM in order to piggyback their user base and let people chat with each other. That was of course self-serving lip service to interop (MS even worked with Yahoo to connect their two services, while they were making noises about how AOL was playing unfair). Now they try to exhort money out of Trillian. It’s funny to hear MSN talk about how expensive it is to run an IM network, considering its awful availability, by far the lowest in the industry (that poor track record works wonders to taint the .Net brand by the way).
After all those years MSN still lacks clear leadership and a real focus on software. Feels like MS Money with more resources. That’s probably because the interaction with the rest of the company is minimal at best. Dump that piece of crud to Barry Diller and focus on growing the enterprise market, that might do some good for the stock.