From the Lousy Reasons dept.:
...if Sun really _is_ going to release OpenSolaris under GPLv3, that
_may_ be a good reason. I don't think the GPLv3 is as good a license as
v2, but on the other hand, I'm pragmatic, and if we can avoid having two
kernels with two different licenses and the friction that causes, I at
least see the _reason_ for GPLv3. As it is, I don't really see a reason at
all.

ussg.iu.edu/hypermail/linux/kernel/