I've installed it on x86 (Gnome), IIRC the free Solaris 10 version. It was a disappointment for me as a novice user. Debian is much much better because it has infinitely bigger software support.
Solaris has its own "apt-get" system, which works but good luck finding software for it.
I also used a bit Solaris on some expensive SUN server (rackmount) but only with telnet. Its not mine and must be run 24/7 so I couldn't really 'play' with it.
The only advantage might be ZFS (but sooner or later Linux will have that too or maybe it already has?). Its supposed to be "revolutionary", but I'm skeptic.
oh, and boot-up time is quick compared to Linux.
edit: Solaris on PC won't start at all if I keep web camera in USB. If something goes wrong with it, it will be hard (impossible?) writing to its OSF filesystem from Linux. Many people use Linux so its much easier to find (free) help.
