The 1.9 million-square-foot Fashion Show Mall in Las Vegas may be getting a new owner as the General Growth Properties Inc. and Rouse Co. merger closes, but it will remain as loud and audacious as ever. The mall's first major event after the merger will be Cloudburst 2005 on New Year's Eve. Mall managers are expecting 300,000 revelers to converge on the party, which will be held underneath Fashion Square's trademark 10-story-high, 480-foot- long cloud.