Ever since iMessage was introduced as part of iOS 5, we've been waiting impatiently for Apple to bring that goodness over to the Mac. With OS X Mountain Lion, announced earlier this morning, it will be a reality. In Mountain Lion, Apple will be replacing iChat completely with a new app called Messages. We've installed Mountain Lion and have been playing with it a bit, and what we've basically found is that Messages is everything that iChat was, but with the addition of iMessage and FaceTime rolled in (still no MSN Messenger support.) Apple has actually released Messages in beta, so you don't need to wait for Mountain Lion to get in on the fun, as long as you're running OS X 10.7.3. Head on over to Apple's Messages page to download it.