Yesterday there was an OpenSolaris install party/workshop/presentation at my school, the HEIG-VD. The presentation was made by the Swiss OpenSolaris User Group which were very nice and open about other operating systems 
Honestly, I didn’t know much about OpenSolaris, so I went there to open my horizon a little bit and it turned out to be very interesting! We mostly discussed about technologies implemented in OpenSolaris 2008.11 and made parallels with Fedora and Linux in general. There were talks about:
- OpenSolaris history
- The ZFS Filesystem, perhaps the most interesting part, it was a live demo of the ZFS filesystem made by Javier Conde, a Sun engineer.
- The OpenSolaris application packaging and repositories configuration
- Virtualization containers, and how to run native Linux apps in them
- The DTrace tool to analyze software
