I interviewed there yesterday and was one of three (I think) that was not currently rotating at DG. Most, if not all, classes are made up primarily of residents that rotated there as students, though there are exceptions. I had heard the same rumors about the program, but figured it was too good of a program to not give myself a shot at. If nothing else you get to hang out in Denver for a day or two and meet some pretty well-known people.
On the topic of Denver rumors, I had heard that it was a very malignant program. The residents actually brought this up themselves and said they didn't think it was true, but that they definitely aren't a cush program and that they work more hours than most. I also didn't see anything that I considered malignant while visiting the department and none of the rotating students thought it was, either.
So, that's that, for what it's worth. Hope it helps...