Think you can guess the date Windows Vista will officially debut next year? If so, you can win an all-expenses-paid trip to the launch event, or one of nine Xbox 360 consoles. The contest is being held as part of Microsoft Europe's new Beta Experience program, which is designed to keep users up to date with Vista and Office 12 news. "As a member of the Beta Experience, you are one of the first to be informed of the new product features, long before the final version is released to the market," Microsoft says. Those 18 years of age and residing in Belgium, Croatia, Denmark, Finland, Germany, Hungary, Ireland, Italy, Norway, Pakistan, Poland, Portugal, Romania, Spain, Switzerland, and the United Kingdom may enter.