Well folks, with WES coming up in May it was bound to get out at some point in time considering it's expected RIM will announce the existence of 5.0 OS at the Florida event held by RIM. With that being said, I really cannot recommend this OS for any long term use - it's not as stable one would hope it too be, some applications don't work after install and device reboots will happen. This feels more Alpha then Beta (or let's just call it early stage OS 5.0), so I suggest looking around, checking it out and reverting back to a more stable OS.
Also if you look at this thread there are plenty of signs of the 8900 version floating around as well.
*OS Disclaimer - Please Read: Keep in mind this is NOT an official release and as such is not supported by RIM or your Carrier. If you choose to install, do so at your own risk and only if you're comfortable in the process of upgrading and downgrading your device software. It is quite normal during operating system development for certain features to be crippled or disabled while others are tested, and these beta builds often reflect that. They are not always better. Depending on your BlackBerry comfort level, it may be best for you to wait for community feedback on a build before deciding to download and install for yourself or simply wait for the next official release. If you require support, you will find it in our CrackBerry forums via our extremely knowledgeable community base - do not contact your carrier or RIM for Beta OS technical support (their first course of action will be to advise you to downgrade to a supported OS). Follow the links below for more information and instructions. *