Windows 7 might be getting all the attention lately, but Windows XP is having a quiet little renaissance of its own -- not only have sales of the venerable OS been extended until 2010, Microsoft is selling an ultra-secure version to the Air Force. The custom build ships with over 600 settings bolted down, and a security patch turnaround of just 72 hours compared to the standard edition's 57 days -- all because Steve Ballmer personally stepped in and approved the project at the Air Force's request. The effort's to standardize and preconfigure the OS has paid off: 85 percent of previous known exploits have been blocked, support