article_snippet.sent: 280ft - height of the four 30-storey towers .
article_snippet.sent: 2,500 - slot machines and video poker .
article_snippet.sent: 170,000 - Square feet of gaming .
article_snippet.sent: Projections for the economic impact on the Las Vegas economy have been revised upwards from an initial $400m (£265m) to well over a billion dollars.