Los Angeles Mayor Antonio Villaraigosa and developer J.H. Snyder won't discuss details yet, but they are talking up plans to reinvent and expand the Valley Plaza shooping center around Victory and Laurel Canyon in North Hollywood. A new Macy's department store would apparently be part of the project. "That will be the biggest investment in retail in the Valley ever - $560 million - an investment that will be far beyond (any past retail development)," Villaraigosa told the Daily News.