Experience with user generated content (YouTube, Second Life, AdSense) and multiple monetization models (contextual advertising, freemium, virtual currency/goods).
Strong product & marketing sense - help you find, articulate and maintain your true north.
Setting up your business, product and marketing org - when to hire, what to look for, etc.
Deep relationships with fellow entrepreneurs and investors. Experience acquiring start-ups (@Google), so can also help talk you through M&A, strategic investment considerations.