Computers set themselves to and from daylight savings time (DST) automatically.
It's obvious if a clock at home, school, office or car is an hour off, and we know to reset them. It's embarrassingly obvious when we show up for church at the wrong time Sunday morning.
I've never used a digital camera smart enough to set itself. Unfortunately, we never notice our digital cameras are set wrong until a month later when we look at the EXIF file information. Then it's too late.
This is much worse when traveling. If I forget to set my camera to the new time zone I may shoot for a week and have files incorrectly marked. Even the date can be off if I'm in Europe.
Remember to reset everything when you return. My D200 was three hours off when I returned from the PMA show in Florida in February 2006. I didn't notice that until I reset it to daylight time and wrote this article in April!
The worst is if you leave the battery out too long and your camera resets to January 1st, 1978. It pays to check your date and time every so often. I use these dates and times for all my filing and it drives me nuts when a clock is off by a few days and I am trying to sort out a trip.
Reset all your digital cameras ahead an hour for daylight savings time.
Be ever vigilant about this whenever you travel, since your digital camera doesn't tell you that it's set incorrectly, and the results are then botched for life.
HOW TO RECOVER
I use a program called iView to organize my photos. iView also allows you to reset the file information (EXIF) in your files. Even iView doesn't make this easy, You can set all your shots to an exact time like 12:34 AM, bit you can't tell it to add or subtract an hour to everything. You'd have to go in and change each shot individually.
Others have suggested that Photoshop Album 2.0 can adjust the EXIF data for many pictures at once with a fixed offset. I have not tried it.
There are many programs out there to fix these problems. Of course if you camera is off by several days or more you or I have probably long forgotten the correct data to which to correct the files.