Chicago’s new sports stadium, “United Center,” is dedicated two years after United announced its 20-year agreement with the Metro-Chicago Sports Stadium Joint Venture to have the center carry United’s name.  The stadium features a huge United logo on the roof, automated ticket machines on site and telephones in the center’s suites with direct lines to United reservations centers.  United did not reveal how much the deal cost, but said it had agreed to pay up to 10 percent of the total cost of the stadium, or $17.5 million.  Given the advertising value of having a company’s name appear in every advertisement and news story about events at the center for 20 years, United considered the deal a once-in-a-lifetime opportunity.