No, it's not 'real', as you put it.
It runs at 720p. It is then UPSCALED to a different resolution. The game is natively 720p, nothing will change that. It's like this for nearly all console games, as the systems simply cannot handle a game at 1080i/p. It's not true 1080i, no settings in your PS3 will make it that resolution, as 720p is what's on the disk.