uring the half-century debate over whether to build a meeting center on the shore of Lake Monona, a persistent argument against construction went something like this: It will be a boon for meeting planners and a small cadre of high-rolling big shots, but how will the city really benefit? Will there be a return on a multimillion-dollar investment of public funds? The answer is that businesses and people throughout Dane County will benefit when the Monona Terrace Convention Center this month joins the Dane County Exposition Center and the Holiday Inn-West to give the area three first-rate facilities. They are turning Madison from a non-player on the national convention scene to a hot destination that's now attracting the likes of the U.S. Conference of Mayors (in June of 2002 at Monona Terrace). The benefits are actually pretty easy to ascertain. Those thousands of conventioneers do not sit on folding chairs in the convention hall 24 hours a day. They need a place to sleep. They like to eat in restaurants. They want to shop for souvenirs. They will, in short, pump an enormous amount of money into the local economy.