The sense that the old rules no longer apply is evident in this trio of office buildings in a prize-winning proposal for the old Fiera Milano site in Milan. Arata Isozaki's saillike form, on the right, appears to be a relatively conventional interpretation of the Modernist slab, until you notice the odd-looking props at the base. The skewed planes of Zaha Hadid's twisted tower on the left, while more elegant than Calatrava's, have the same forced structural logic. So does Daniel Libeskind's bowing, curving skyscraper. (Since elevators move in straight lines, there is a freestanding elevator core, just visible in the rear.) As new as this may be, it all feels a little forced. Being iconic is getting harder all the time.