Interesting photo...it does look like someone standing there, but it also looks as if someone is in the window next to it as well. Can you zoom in on the photo to give us a better look?
The window next to it could easily be the sun's reflection, so clearly that is a possibility. However, the window with the figure cannot be easily debunked because that is not white light, but something more eerie. Not a shadow, nor a solid figure... Interesting.