MSN Messenger 3.5 for Mac makes it easy to take advantage of the full power of instant messaging. By using MSN Messenger, you can see when your friends, family, and co-workers are online and then communicate with them instantly. MSN Messenger can also notify you when new messages arrive in your MSN Hotmail Inbox, if you have a Hotmail account, and provide the latest news and headlines from MSN.

What’s New in this Version
– Save every word and emoticon
– Make quick updates
– Organize by dragging contacts
– Elegant OS X user experience
– Customize your text
– Share files or pictures
– Talk to MSN Messenger on any platform
– Emoticon images

More info here.