I wish the story had detailed whether they will actually be lengthening the concourses, or just cramming in more gates to the existing space.  I fear that it's the latter.

One of the virtues that makes DIA a great airport are the wide concourses that are (usually) spread out enough to avoid the severe overlaps and overcrowding (and confusing, overlapping loudspeaker announcements) that plague many other airports.  Unfortunately, they've already created that problem at the very ends of some DIA concourses.  On C, they've jammed so many gates into one end that the Southwest queue lines practically overlap each other, and there's virtually no seating (it's been moved out to the center aisle of the concourse).  Announcements are confusing as hell when there are planes departing around the same time, as they often are.  It just overcrowds the whole area, further squeezing out services and food concessions as well.  

I'd rather they just build a D concourse.