We have completed the database update we needed to perform to correct the "Date Taken" for all your photos. Here’s how it works:

There are 3 EXIF dates available to us to use as the date the photo was taken. We look for Date/Time Original, then Date/Time Digitized, and finally Date/Time. We grab the first one that’s available to us, but if there is no EXIF data, we pop the date posted in there for you instead. You should also note that Date Taken always appears in the photo owner’s timezone.

(Thanks groc, for this slightly weird Santa.)