On the 12 February 07 Yahoo Inc put out a press release "Yahoo! Mail Brings E-Mail And Instant Messaging Together, Providing People Easier And More Engaging Ways To Connect" which highlights the upcoming Yahoo! Mail and Yahoo! Messenger integration that is rolling out across all Yahoo! Mail beta accounts over the next 3 months.

"This deep integration across Yahoo!'s e-mail and instant messaging services enables e-mail users to easily connect to contacts in Yahoo! Messenger's thriving IM community, without leaving the Web mail experience. People can choose to let others know if they are online and available to exchange messages in real time, and users will be able to see the online status of everyone in their contact list as well. Each instant messaging dialogue will take place in a new conversation tab within Yahoo! Mail beta, allowing people to chat with multiple friends simultaneously, without leaving the e-mail experience. Users can also convert e-mails seamlessly into IMs when friends come online (or vice-versa)."

You can check out the Yahoo! Mail Beta Blog article Messenger and Mail…together at last!, there is also a screencast available which is worth checking out as it takes you through the basics of what's being rolled out, how it will look, feel and work, it's also mentioned over at the Yahoo! Messenger Blog, article Yahoo! Messenger, meet Yahoo! Mail so swing by that one also :)