As a proud owner of a PS3, and an aspiring graphical artist, I have to question the legitimacy of these photos. In a day and age with all the easy to come-by multi-mega pixel cameras and powerful PhotoShop infused computers, something this important should be handled with a little more clarity, which these pics are not.
Since some of the reflections show off some guy's bedroom (see what looks like an easel and posters on the wall), I would think evidence capture could be handled more efficiently and less like you are under surveillance. Also, there are some odd icons on the upper left and bottom right of the screen that just don't add up. Oh, and on what would seem to be the normal Friends Column sub-options (Block List, Add a Friend, Player's Met, Message Box)... the icons and the text look a bit crooked. Now the crookedness could be due to the angle of the shots taken or maybe this 'mystery person' happened to have scrolled through the icons which caused the distortion.
I won't go as far as to make claims as to how this was pulled off... but considering the fact that the PS3 allows you to view images from it's picture viewer (via the XMB) and that every pic this guy shows are of exactly the same screen from different angles (camera-wise)... it doesn't look promising.
Overall... the ever so slight appearance of what may or may not be clouds in the black XMB background don't sell me on this being taken "within the game". Some alternate pictures of the transition to the game from Home (which I'm assuming it was launched from since the achievement carries the Home logo), or even from the game to the XMB where these are claimed to have been taken from would help legitimize this "leaked photos". Until then... this just screams fake.