Open Solaris vs Linux - A Comparison

OpenSolaris and Linux to a layperson can seem similar in many ways. They both use more or less the same end user applications, have similar desktops, and are open source. But scratch the surface and you find that they are entirely different products all together.
Some of the notable differences which an end user may encounter are as follows :

1. Directory structure differences. For example, in Linux, the Home directory is located at /home whereas in OpenSolaris it is at /export/home.
   
2. Linux and OpenSolaris use different commands for doing the same things. Some commands are similar in name but take different options.
3. Linux supports more hardware than OpenSolaris. This means, Linux runs on more machines than OpenSolaris.
4. One of the main reasons for using OpenSolaris is ZFS. Linux doesn't support ZFS yet.
   
5. Taking snapshots of filesystem in OpenSolaris is a snap. Again courtesy of ZFS. Linux users are, by default, left in the lurch on this front.
   
6. OpenSolaris supports a variety of virtualisation technologies with different degrees of isolation, flexibility, performance and ease of use. Eg: VirtualBox, A port of Xen called xVM Hypervisor, Zones et al. Linux supports VirtualBox and Xen but not Zones.
7. Linux has more applications than OpenSolaris. Period.
8. OpenSolaris boots slower than Linux on the same hardware.
   

Tuxradar runs a detailed comparison between Linux and OpenSolaris with a few accompanying tips and tricks. Check it out.