Apple has today announced the summer release of its newest version of OS X, dubbed Mountain Lion (more details here). While scanning through the features listed over on The Loop, one stood out to me above all else – Messages.

Messages is, essentially, iMessage on your desktop. You’ll be able to chat to someone with their Apple ID or phone number, just as you do from your iPhone. Messages replaces the former iChat client entirely, but your iChat screen name still works as your identifier for Messages. What’s probably most important, however, is that users of Messages who have an iPhone will find that their conversations are kept in sync between the two systems.

Like iChat, Messages will handle protocols for AIM, Yahoo, Google Talk and Jabber, too. So you’re not really losing anything, but rather just gaining that magnificent sync feature. For the existing 100 million iMessages users, this is huge.

Apple has released a public beta of the new Messages client, and you can download it today. Having trouble downloading on the page? Here’s a direct link. We have it, we’re using it, and we’ll be looking into the feature as it moves along.