"If there is one central reason why Linux has done such a great
job of eating Solaris's lunch, dinner, dessert and midnight snacks,
it can be summed up in a single word: agility. Drop Linux most
anywhere and it lands on its feet, thanks to all of the different
implementations that allow the kernel to be used in everything from
embedded devices to clusters. Solaris's biggest selling / usage
points are things that still mainly appeal to programmers (Dtrace)
and people with high-end storage (ZFS) or processing requirements
-- and in licensing that's not compatible with Linux on top of
that."