Comment It's the hardware (Score 2, Interesting) 340
Solaris is dying, but it's because of the hardware. The "big iron" sparc hardware is simply obsolete. Paying tens of thousands of dollars for a 2ghz sparc system is looking less and less attractive. Solaris x86, of course, cannot compete with Linux.
AIX is still relevant due to the great LPAR virtualization and great POWER hardware. Nothing from HP or Sun comes close.