It has been a long time coming, but the first build of Windows Live Messenger 2010 has leaked, confirming many of the features we have seen in our coverage over the past eight months.

The build number, 15.2.2583.119 has been floating around the Internet since yesterday, after reports from LiveSide confirmed the leak had occurred earlier in the week. We at Messenger Stuff have installed the beta and had a close look at what Windows Live Messenger 2010 has to offer.

Below are some important notes concerning the leaked build:

• The build is perhaps many months old. Believed to be milestone 2, website cnBeta has posted screenshots of milestone 3 from over a month ago. We can only assume much more has happened since.
• Only certain Live IDs are able to sign into the beta as is the case with most internal releases. Wikikou has posted a protocol down-grader to allow users to sign into the leak, however conservations are highly unstable.
• The leaked version is extremely buggy, despite its initial polished appearance.
• There appears to be signs of Facebook Chat integration.
• Tabbed chats are confirmed.
• You can revert to the classic style contact list.

We at Messenger Stuff don't provide links to leaked beta builds, particularly ones that are unstable. Even with the workaround to sign in the leaked beta is too unpractical to use in its current state.

With the bugs aside, Windows Live Messenger 2010 looks almost ready for a public release, and I think we can expect a public beta soon.

View our gallery of screenshots of the leaked beta