Peter Whoriskey tackles the question by contrasting Denver's Coors Field with Seattle's Safeco Field. Coors Field is a poster-child for development boosters, whereas Safeco is the skeptic's counterexample.
Bottom line: Safeco was built in an area too industrial for consumer-oriented spillovers to take root. Coors was built in a historical but run-down area ripe for re-development. It may have been a catalyst, but then chasing out the crack dealers might have revitalized the neighborhood on its own.
Here's the story, from today's Washington Post. It's a balanced piece, without hyperbole; worth a read and a think.