Proposed buildings will be second-tallest in US
                                
                                
                                    (Newser) -
                                    San Francisco officials are cementing deals to build a pair of skyscrapers that would challenge New York's 1,250-foot Empire State Building as the US' second tallest, Bloomberg reports. The city has selected a plan for a slender, 1,200-plus-foot obelisk  to be built in the Market financial district, with...