In addition to Berkeley, nearby Emeryville is a very nice place to live. It's close to a lot of public transit (freeways, MacArthur BART, bus lines on San Pablo) and 15 minutes across the bay bridge to SF and 5 minutes from Berkeley. Large companies (like Pixar and Bayer) and a few startups (like TubeMogul) are here already. A medium/big startup considering the peninsula could make a big splash and see high ROI choosing Emeryville.