OpenSolaris is not only powerful, but it is very innovative. Somebody smart figured that simplistic chroot or BSD jail concepts could be extended to the level where every single part of HW is virtualized. Linux kernel also offers somewhat similar proposition called vserver, but we all know that until a proposition is not a part of main-line kernel tree it will never be a solution. We have chance to play with OpenSolaris now and it trully opens a new horizons for us to explore.
We now have Zones fully integrated with NexentaOS.