Yes, this has been a real pain especially if you are like me and use the ATv for business use.
My investigation so far (and please don't hold me to this) is that there used to be a bug in the ATv but it is now fixed. In my case at least, I had odd results across a range of 2500 photos so I simply pulled all the odd ones out and had a good look at them. In every case, the photos had been taken by a high end Canon or Nikon camera and the EXIF data (ie the photo meta data) had been modified since the photo had been taken either by an editor or a "rotator" etc. In every case the Orientation tag did not match the orientation I wanted the photo displayed at eg Orientation within EXIF was 90deg when 180deg was required. For those of you who understand what I am talking about, this could have happened for a number of reasons eg an old editor program rewrote the EXIF in the wrong place after editing, A new editing program had written EXIF data in a file that didn't previously have EXIF data. The EXIF standard has been "changing" for quite a while and has only started to become stable in all cameras and software in the past few years (my experience anyway). Sure enough, all the photos in question were not taken or edited by me. Over a period of time I had simply rotated these photos to correct orientation when they had arrived in my shop. I never thought to check the EXIF data.
My quick and dirty fix was to delete the EXIF data from all the "odd" photos using Phil Harvey's very excellent EXIFtool and then simply rotate them all again using Adobe Elements. I rotated them 2 ways. One doing a hard rotate and rewrite without any EXIF update and two only editing the EXIF data (the correct way). Both ways worked on the ATv (which is the way that it should be).
I spent many hours on this and checked an awful lot more than is documented here (as well other gear I have eg overhead projectors). All of the tests pointed to the ATv and the associated iTunes software finally getting it right.
There is a lot more to test and I know many of you out there with time on your hands will no doubt prove me wrong BUT at the moment this is my conclusion and I look forward to reading about yours.
Good luck.
