OpenSolaris 2008.05, aka "Project Indiana" will be officially released to the world later today (US time), but it's already available now for download from it's dedicated site - www.opensolaris.com.
For the uninitiated, I'll quote the OpenSolaris docs...
The OpenSolaris 2008.05 release is an OpenSolaris binary distribution. This release provides a Live CD for x86 platforms. This Live CD includes a basic core operating system and GNOME desktop environment, with the option to install the OpenSolaris operating system from the Live CD. Or, you can mount the OpenSolaris OS on a VirtualBox. After the OpenSolaris OS has been mounted or installed, additional packages, including developer tools, can be downloaded to the system by using the Image Packaging System (IPS). A new beadm utility enables you to manage multiple boot environments.
Sounds like your average GNU/Linux LiveCD distro, but it's not. It's OpenSolaris, and what's more, if you want support, you can get it for as little as $49 per incident.
So head on over and get downloading. Whilst it's downloading, take the time to browse around the new site. There's a wealth of information in the Learn (aka knowledge) section, but if you've got a question that isn't answered by the documentation, or have a cool use for your OpenSolaris 2008.05 installation, head on over to the Share (aka forums) section and let the peeps know.