Google Chrome, HTML5, and the new Web platform

A friend and I were debating the other day: Is it appropriate to refer to Google's Chrome OS as a platform? We in the tech press often use the terms "operating system" and "platform" interchangeably, but they aren't always the same thing. Ubuntu is an OS, for example, but it's not really a platform. The platform in that case is Linux.Rolling Stones Oprah Winfrey U2 Tiger Woods Steven Spielberg Howard Stern 50 Cent Cast of The Sopranos Dan Brown Bruce Springsteen