Theory:
The videos and photos released today were staged and taken back on Friday before he left for Walter Reed. The EXIF data on the photo released today was manually edited to make it appear that it's recent when it actually isn't.
I saw what looked like physicians standing outside the hospital on MSNBC. It is possible to get some random person off the street and put him in a doctor's smock (physicians are strong candidates for the worst-dressed of all professionals; they can get away with it because they are physicians)... and it will be convincing. Why would there be physicians outside the hospital standing in front of it? Real physicians would have better things to do with such a high-profile person being treated, wouldn't they?