Honestly, I don't know that much about Mexico City. I know it's large, it's crowded and it has issues with smog and pollution. That's about it. Looking at pictures gives some kind of impression, but mostly a very incomplete (and potentially enscanated) one.
That's what I like about the photographs by the helicopter pilot Oscar Ruiz. Granted, not every picture has a strong composition, but the images can give you a different feel for the city.
They just give you just that little bit of extra perspective of the life in Mexico City. Like the image above. It does look a bit like a rendering, but it's an actual picture of a part of the low income housing complex in Ixtapaluca, which has a whopping total of more than 10,000 houses.
Or the image below, showing Cerro Chiquihuite, where a wall was built halfway up the hill in order to stop people from continuing to build uphill.
Or, all the way at the bottom, the market at Barrio Tepito. The area is allegedly very criminal and (therefore) dangerous, but the market should be awesome.
All in all, sometimes having a little bit of an overview can give you a better sight of the city than eye-level images.