Venture capitalist Roger McNamee in his book The New Normal writes,
"In the new normal, neither big businesses nor IPOs will get all the glory. Today, size matters less than at any other time in the past 50 years. Thanks to technology, even small businesses can have a global footprint if they leverage the Internet and available tools that are dropping in price even as capabilities increase."
Lastly, in one of those unintended consequences that governments create, Sarbanes-Oxley and the grand inquisitions of Eliot Spitzer are gifts to startups. Smaller companies can focus. Brain cycles in large public companies go to waste attending to compliance issues and other cover-your-rear work.