A few days ago, Amazon and Microsoft declared to the world that a Kindle app was underway for the Windows operating system. Just earlier, the online retailer has confirmed that an OS X version of the application is coming too, as reported by TUAW, though details are unfortunately bare currently.
The Kindle is, as you may know, a piece of hardware designed to aid with the mobile and digital reading of eBooks, and it is coupled with Amazon's software which provides a vast range of them ready and available for download over-the-air. It's a handy service for those who use it, though currently it's limited in the devices it's available on. Amazon, perhaps seeing a threat from the new Barnes and Noble 'nook' reader, aims to fix this by having compatibility with desktop computers.
This is a great move for Amazon and users of the Kindle service, though it means if you purchase a book through that company, you can't use it with any other e-reader, causing problems if the need arises. At the moment, there's no estimated shipping date on the software, but hopefully it won't be too far away.