One of the problems with OpenSolaris is that, apparently, a working system
cannot be built without non-free Sun development tools. I haven't seen any
evidence of a sustained effort to fix this. "Free, but shackled" is Richard
Stallman's apt term for this kind of problem.
On the positive side, I'm sure we'll see more healthy competition between
OpenSolaris and Linux at the kernel level, as between Linux and the BSD