Big things are happening in Denver. New rail lines are snaking out in all directions. Union Station is transforming into a modern transit hub. High rises are sprouting from once-vacant lots. To figure out what it means, we chat with Ken Schroeppel, instructor at the University of Colorado Denver's College of Architecture and Planning, not to mention the development guru behind Denverinfill.com and Denverurbanism.com. This isn't some wonky discussion of building permits and zoning rules. There's talk of Denver's long-dead streetcar lines, the multimillion-dollar ramifications of DIA's doomed baggage-handling system, and rumors of backroom deals swirling around Union Station's redevelopment. And yes, flying cars.