I wanted to take this moment to recall a thing I noticed about NTFS a couple years ago. It seems that NTFS treats timezones as a viewing parameter. (I presume they store times internally in GMT or something similar.) So if you move from Finland to California and change your computer's timezone, all your files will have a new time.
This might not be so objectionable, except for the problem that it does the same thing for daylight's savings time. So today, all your files from a week ago now happened an hour earlier in the day. Does this make sense at all? You didn't change your position in the universe (or those files). But go ahead and check, it's true.
A couple years ago, I had to make Picasa ignore filesystem changes of exactly an hour to keep it from freaking out and rethumbnailing your whole computer twice a year.