Microsoft, Yahoo Complete IM Interop

Microsoft announced on Wednesday that it has completed the joining of its instant messaging network with Yahoo! Messenger, meaning any of the services' combined 350 million users can now send messages to those on either network. The interoperability was being beta tested since mid-July.

"This chapter of the story comes to a close," said Windows Live Messenger team member Leah. "Anyone using the latest version of Windows Live Messenger or Yahoo! Messenger (in most countries) will be able to add friends, send messages and select emoticons with those from either network like crazy – and we encourage you to do so!"

Initially, the two companies have focused on enabling text messaging between Windows Live Messenger and Yahoo! Messenger with Voice. Voice capabilities across the networks will be supported at a later date, but cross-network video conferencing is not currently in the plans.

The agreement marks the first time major players in the highly-competitive IM industry have officially partnered up to enable cross-network communication. Interoperability has always been a hot topic among instant messaging providers, but had never yielded a compromise.

The pressure is now on AOL, which has long been the dominant force in instant messaging. AOL and Google signed a deal to link their IM networks as part of an investment by the search giant in the struggling ISP, but no date for interoperability has been set.