It's official, Yahoo Messenger and Microsoft Live Messenger now interoperate! As of today, the limited beta is no more and it's fully available to all users. That's right, starting today the combined community approaching 350 million user accounts (arguably the world’s largest IM community) can take advantage of Yahoo! Messenger interop with Windows Live Messenger. Woohoo!

Here are some interesting stats that resulted in a recent poll commissioned by Yahoo! and Windows Live which was conducted by Harris Interactive:

Some IM Users Are Willing to Forego Their Guilty Pleasures for (IM) Inter-Connectivity Feature:

• 29% said they’d be willing to give up watching American Idol
• 16% said they’d give up ice cream for one month
• 15% are willing to give up their morning cup of coffee
• 15% said they’d give up their morning paper

Some other interesting findings:

One in four IM users surveyed said that being able to use one IM service to connect with friends on other IM services is the next great thing  since the creation of the cell phone.
57% of the IM users surveyed have a friend or family member on a different IM service.
More than one-third (35%) of students (over the age of 18) use more than one IM service.

Hat tip to yodel.yahoo.com:

Today I woke up, logged onto Yahoo! Messenger, and pinged my friend Blake Irving, head of Microsoft’s Windows Live Platform Group, to applaud him and his team. Congratulations are definitely in order, as today marks a true milestone in Internet history. For the first time ever, interoperability (a.k.a. interop) between consumer instant messaging (IM) services is possible.

In July, Microsoft and Yahoo! introduced interop on a limited basis and received an overwhelming response. In just two months more than 90 million messages were sent and received across our networks — a level of usage that is a dream for us Internet geeks.