According to eweek: Analysts: Sun's Open Solaris Plans Face Problems.
The problems mentioned are largely that of community building. And that community exists already, and is building up and getting stronger all the time. These analysts who say that Sun can't build up a community simply don't know what they're talking about. We already exist.
Webbink [Red Hat's General Counsel] agreed. "It's not about the license, it's about the community," he said. "So how is Sun going to instantly attract hundreds or thousands of developers to Solaris when they have never had the opportunity to work with the source code before?"
The following numbers are from memory, but the general magnitude is what counts. Well, Sun have about 1000 of their own developers (not all involved with the kernel, of course) already, with getting on for 100 of us external participants in the OpenSolaris pilot community. Red Hat have 200 developers? The Linux Kernel development community isn't that large either. And Red Hat have had their own problems in building a community.
So the point? OpenSolaris has already started to build a healthy community, and it's already getting to be a decent size.