What's this effect called?

http://maps.google.co.uk/maps?hl=en&...8. 15,,3,4.76

http://maps.google.co.uk/maps?hl=en&...,200.99,,3,2.6

I think London would look better if concrete structures such as the
Hammersmith flyover used this effect, but I don't know how expensive it
would be.