As seen on /. IBM is questioning whether or not it is really open.
I think the real question is, does it matter?
I really don’t see a need for it. The market is positively crowded with OpenSouce Linux, *BSD. OpenSource should not be a repository for declining projects.
From an ISV perspective, you have to ask “why”? Precisely what benefit in terms of lower costs and increased revenue does being on Solaris bring? Same question for IRIX, HPUX, AIX, … . Most of the ISVs I have spoken with recently have talked about platform convergence. Two ports, one on linux and one on windows. The others are fading fast, there really is little in the way of technological/market reasons for new ports to declining platforms. At least in HPC.
That said, some of the LiveCD OpenSolaris projects are actually quite nice.