the second one looks normal,, but those other 3 just look weird,,they could be photoshoped,, or they could be real-meaning 2 things,, either someone allowed them in, or obama has security issues he needs to fix, because next time that might not be just a sign being held up.
if you save the image,,then do a close up of the top corners -they are very blurred in a cirlce, the circle goes above the image of the sign.. might not mean anything but it doesnt look that way when you look at the other posters or the rest of the 911 sign.. im no expert in looking at pics, but when everything in the pictures are consistant,,then theres something that doesnt -it raises suspicion,, still not enough to prove the case either way