No More Free Solaris
Looks like Oracle understands that Sun's "make it up in volume" theory just wasn't working out:
Rebranded Oracle Solaris operating system, the UNIX OS will now be available for a 90 days trial version and then users have to pay to buy a licence. Earlier, under Sun, the OS was available for free but users had an option to buy support from Sun. This may seem OK for enterprise customers as cost of OS is miniscule compared to cost of services. Companies like Oracle generate extremely thick revenues through services and support.
I'm not sure what kind of future Solaris has in any event, free or otherwise. Linux mostly qualifies as "good enough", I think.