I like the idea of playing an FPS in and around well known landmarks.
They wanna make that shit to scale though, for instance, if I embark to hunt that sniper at the top of the Eiffel Tower, I want to be running up there for at least 25 minutes before I finally creep up behind him and stabby stabby!
Also, I want to stop for a coffee on the way back down and a chocolate waffle.