While ReactOS 0.4.9 images have been available for download the past week, today this "open-source Windows" operating system project officially introduced this latest version.

With this three-month update to ReactOS there are a lot of improvements including the ability for ReactOS to finally self-host itself, as in the ability to build ReactOS on ReactOS. Up to now ReactOS wasn't able to self-host itself with ease and had a number of issues that have now been overcome.

ReactOS 0.4.9 also has better stability thanks to various code improvements, a better FastFAT driver, shell improvements, and a variety of other improvements.

More details and screenshots for ReactOS 0.4.9 can be found via this morning's release announcement at ReactOS.org.