So, the Illumos announcement was made. The best analysis of the announcement I read so far is The Register's.
For the moment, I am not impressed at all. What I was hoping in was a "real" Solaris-like system, not a mix of Solaris and Debian/Ubuntu Linux. That's what Nexenta is, after all, and that's what it will still be if it will switch its base to Illumos.
Time will tell if this effort will bring us something decent. I still hope (but less and less each day) that Oracle will keep on investing in an Open-Solaris official distribution. Yes, Open-Solaris, with that dash in between: something that is both a real Solaris, and Open source.