A OpenSolaris Hackathon was just announced. The event will take place in London, and the way the announcement was made seems to open up for good hopes:

Apologies for the late notice, I'm proud to announce what will hopefully be many OpenSolaris Hackathons!

even though they feel the need to say:

This is a community event held by community members and is in no way affiliated with Oracle.

Keep your fingers crossed…