Based on the U.S. Energy Policy Act of 2005, Daylight Saving Time (DST) has been extended by approximately four weeks. As a result, DST will start three weeks earlier this year, on March 11, 2007, and end one week later on November 4, 2007.
Will this affect your applications? To find out, read about Visual Studio and the DST change. You can also get more information by Preparing for daylight saving time changes in 2007 and KB928388: 2007 time zone update for Microsoft Windows operating systems.