Not especially big. Don't be misled by the anecdotal comments from out-of-town Jackson fans visiting L.A. to attend the memorial service - or at least to be part of the happening. No question that some of the downtown hotels are enjoying some unexpected business for a day or two, with economist Jack Kyser estimating a $4 million bump in the form of hotel billings, restaurant tabs and souvenir sales. In the midst of a bruising recession, that's better than nothing, but for an economy as large as that of L.A., it's not much. Already, we're seeing signs that the turnout, while substantial, is not nearly as large as some had imagined. Yes, imagined is the operative word. LAT has story on the business side of the show, and it comes up during my Tuesday business chat with KPCC's Steve Julian.