Historically, daylight saving time has started at 2 A.M. on the first Sunday in April and has ended at 2 A.M. on the last Sunday of October. However, the US government's Energy Policy Act of 2005 extended the dates for daylight saving time in the United States. Beginning in 2007, daylight saving time will begin on the second Sunday of March and end on the first Sunday of November, which extends daylight saving time by roughly four weeks.
In the "Preparing for Daylight Saving Time changes in 2007" Web page (http://www.microsoft.com/windows/timezone/dst2007.mspx), Microsoft notes that it will be producing an update for Microsoft products affected by the new US daylight saving time transition dates. Because the updates haven't been released and because the Win32_TimeZone class properties are specific to the current year only, I can only assume that GetDLSDates.vbs will work properly in 2007.