I was checking the JDC (Java Developers Conference) web site, when i found a link to Roman Strobl's blog (as he is one the speakers in the conference). In this post, i found a screenshot of Solaris Express on his laptop.
This is how the screen shot looks:
Solaris Express codenamed Nevada is a program that lets you preview work in progress code base fully functional and tested. This way you can try and test new features only weeks after they have been developed. Solaris Express can be download for free from here. I have found also that part of the code base for Solaris has been opened for review by open source community through OpenSolaris project.
Enjoy it :).