Why Always A Competition?
Everywhere I look, it's "How OpenSolaris can crush Linux" or "What Linux has to do to fend off BSD/Solaris threats" or some such. I get the strange feeling the writers of those stories have forgotten that open source does not work like the commercial market. There doesn't have to be any X vs. Y BS here. Since Linux, *BSD and Solaris (and Hurd, and Darwin) basically all run the same sorts of programs on top, I fail to see why they have to be considered "enemies". I thought the concept of a monoculture was bad?
What we have here are 5 different kernels, with similar compatible services on top. Ultimately, it's more choice for the user, and I think that is a good thing.