The New Orleans Planning Commission has postponed for a month a decision on a proposal by Churchill Downs Inc. to install up to 700 slot machines at Fair Grounds.Supporters and opponents of the plan spoke at a lengthy hearing, the Times Picayune reported. Under a state law, the track is eligible to have 500 slot machines as of July 1, and add another 200 in 2006.The commission put off a vote until its May 10 meeting. It could amend the zoning ordinance to classify slots as an accessory use at a racetrack, or it could approve CDI's plans to build a 33,000-square-foot addition to the Fair Grounds grandstand, the newspaper reported.After the planning commission takes action, the New Orleans City Council must consider the plan. The council must vote by July 5, but it could delay introduction of the ordinances and thus slow the process.The commission's staff recommended the slots operation be limited to 12 hours -- -11 a.m-11 p.m. daily. CDI chief operating officer Andy Skehan said the company is concerned with those limitations, and would prefer to operate the slots 24 hours a day as do other racinos and casinos in Louisiana.Skehan said it wouldn't be economically feasible to spend $20 million on a building to house the slots if they operate only 12 hours a day, the Times Picayune reported. Skehan also said though the results of the recent meet at Fair Grounds were encouraging, the track still needs new revenue to make it "a sustainable business."