From the event site:
Open is the new better — not just for technology, but for business. We’ve partnered with Salil Deshpande, Managing Director at Bain Capital Ventures, for an event that will change the way you think about open source.
Featuring a new, expanded format, the #sfbeta Open Source Startup Summit features an afternoon of in-depth talks and panels, followed by an evening of socializing and demoing in the classic #sfbeta tradition.
Information and registration here.