adywan said:

well the top ones, they used the old matte painting with the old style building which also didn't match the buildings we saw in the previous shot. The bottom one, well they are the same buildings but sections flipped. This was because the light is coming from the right (although it is hard to tell in the 2004 shot because they completely blew out the high levels), when in the next shot the light is coming from the left. So the buildings were modified for continuity

See, I love this stuff! The attention to detail is amazing!