At Mix09, Microsoft released the Windows Live Messenger Web Toolkit — a set of controls and libraries that enable you to connect Windows Live Messenger users and their friends with users of your Web site. Essentially, a web developer can give you a pretty slick web IM experience using Windows Live Messenger on a website you are visiting. Visitors of a website with Windows Live Messenger functionality built in can IM with their contacts or even other visitors on the website. This creates a new level of engagement for visitors on that website.
 

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