As I noted here and here previously, the kick off for daylight saving time (DST) is changing this spring (2007). The start and end dates for the United States will transition to comply with the Energy Policy Act of 2005 (a US gov't web site link). In short, DST dates in the United States will start three weeks earlier (2:00 A.M. on the second Sunday in March) and will end one week later (2:00 A.M. on the first Sunday in November).
In general, computer systems should be updated to reflect the new DST rules. For most customers, this means applying software patches to select Microsoft products, including various releases of the Microsoft Windows servers and operating systems, Microsoft Office and other applications. In a few important cases, customers must take more considered action, as outlined on our newly renovated DST 2007 website. (http://www.microsoft.com/dst2007) This public page on the Microsoft.com site will be revised regularly to include new product updates, compatibility information and links to Knowledge Base articles.
At the office and at home, my machines that subscribe to Automatic Update (which is all of our Window XP machines at home) received the Windows update, and my Windows Vista machines was just updated, too.
Many Microsoft applications derive date and time information from the system clock, which "reads" the date and time information from the underlying operating system that it resides, so the changes need only be made to that underlying system. So you may not need to update many applications on your PC - check with your vendor to see if an update is required. For Microsoft products, many updates will be released through a combination of channels including Knowledge Base articles, Windows Update, Microsoft Update, Windows Server Update Services (WSUS), and the Microsoft Download Center.
Want to find out the accurate time in the US? Go to http://www.time.gov/ and select your time zone.
"This public service is cooperatively provided by the two time agencies of the
: a Department of Commerce agency, the National Institute of Standards and Technology (NIST), and its military counterpart, the United States U. S. NavalObservatory (USNO). from the clocks of these agencies contribute to world time, called Coordinated Universal Time (UTC). The time maintained by both agencies should never differ by more than Readings 0.000 0001seconds from UTC (see recent comparisons)."