Check out some more information regarding Windows Live Messenger!

What it is
Windows Live Messenger will be the next-generation MSN Messenger. It will have everything you already love about Messenger-your contact list, emoticons, and instant access to your friends via text, voice, and video-plus new ways to connect and share documents with almost magical ease. As always, it will be free to download Messenger and use most of its features.

What you will be able to do with it

• Send all your familiar winks and emoticons, plus some cool new ones
  


• Have real-time text, video and voice conversations*
  


• Call your friends' mobile or land-line telephones with Windows Live phone call, and make affordable domestic and international calls**
  


• Easily share documents of all kinds with Sharing Folders
  


• Make free PC-to-PC calls with other Messenger users
  *Both parties must have compatible Web cameras, speakers, and microphones.
  **Windows Live phone call is provided by a Microsoft partner.
  

System Requirements

• Multimedia PC
  


• Pentium 233 MHz process (500 MHz recommended)
  


• Microsoft Windows XP
  


• Minimum 64 MB of RAM (124 MB recommended)
  


• Up to 50 MB of hard disk space for installation, 15 MB to run the program.
  


• Microsoft Internet Explorer version 6 SP1 or later must be installed on your computer, though it does not need to be your default.
  


• Minimum 800 x 600 screen resolution
  

(via: Inside Windows Live Messenger)