With Messenger, users can communicate, bring data with them, invite their friends...
...and their friends invite their friends, and...(you get the idea - huge network!).

Messenger Blog
With the release of the Windows Live Messenger Web Toolkit V3.7 we are now distinguishing between levels of browser support – full and limited. Going forward, fully supported browsers should behave consistently across all scenarios while limited support browsers may have minor issues including unobtrusive UI defects. Limited support browsers are determined based on market share and whether the m....
We are happy to announce the immediate availability of the Windows Live Messenger Web Toolkit (MWT) Version 3.7 in all markets! V3.7 improves the Messenger Web Toolkit by adding the following. Offline IM - Users can now IM offline contacts, just like they can in the Messenger desktop client. ASP.NET Ajax Library Integration – Starting in V3.7, the Messenger Web Toolkit UI Controls are b....