Microsoft has released a pdf documents highlighting the features of the new Windows Live Messenger 2010 Wave 4.

The following websites have also gone live, highlighting the new features of the new Messenger & Hotmail !
www.windowslivepreview.com
www.messengerpreview.com
www.hotmailpreview.com
The new Windows Live Messenger is designed to address all these challenges, make your conversations more meaningful, and give you the tools to bring together all your social updates and help you connect with the people that matter.
Microsoft has reinvented Messenger to do four important things:
- Deliver the best IM — making common tasks easier and personal interactions more meaningful
- Seamlessly integrate into the things you’re already doing on the Web and on your phone
- Give you the ultimate social dashboard for staying in touch while eliminating the noise
- Provide tools that are designed to put you in control and keep your private life private.
So what’s New in Messenger?
To begin with, the new Messenger has:
- Tabbed conversations
- Integration of Bing results
- High-definition video chat
- Video message
- Badges
- Games
- and more!
The document also has a feature-wise competitive comparision chart, comparing Windows Live Messenger vs Yahoo Messenger, Skype, Google Chat & Talk, ICQ, AIM & Facebook.

Download: Whats new in Windows Live Messenger 2010.
