Also, ZFS is just one of the many ways Solaris rocks. There's SMF, for process/service management which doesn't rely on a bunch of shell scripts, and can actually detect when an app has crashed and needs restarting. Oh, and zones, instant, near-zero overhead virtualisation. Oh, and woring NFS v4 , you know, with ACLs and stuff. then there's RBAC for granular delegated security, and dtrace for deep system monitoring/analysis
But yeah, you're right, Solaris is way old..