Microsoft has made MSN Messenger 4.0 available to Mac users.
The new version of the instant messenging client offers Office 2004 integration – it is possible to use MSN Messenger to see if team members are online, initiate an instant message conversation with them from within your document, and then save it as part of your project file.
Also available are new emoticons, one mechanism that handles all .Net, MSN, and office alerts, improved file-sharing across corporate firewalls, and a spam filter. Microsoft also claims it is easier to setup.
The new version requires Mac OS X 10.2.8 or higher.