Microsoft was announced that Vista will arrive to the shops at the end of Jan 2007 so all software engineers are working hard to update their programs for Windows Vista platform.
Yahoo!! Messenger team is also in the progress and i must tell you that what is coming is so cool. way to go guys 
Some new features;
* Brand new emoticons, program icons and alert sounds
* Instantly change the look and feel of your Yahoo!! Messenger interface.
* Automatic groups are created in your contact list based on your Yahoo!! interests (i.e. Yahoo!! Sports Fantasy Football league)