Look at Crown Center, it has been going on for 30 years and is close to what I would call a disaster--ugly architecture for the most part, relail and residential sealed off from the outside world, it is the suburbs gated from the city in the heart of the city.
From what I can gather, Crown Center is somewhat similar to Renaissance Center(the massive series of circular highrises) in Detroit. Renaissance was criticized by design people because in its effort to revitalize Detroit, it maintained an overly inward focus and self importance. Rather than extending its reach into downtown Detroit, it attempts to isolate itself. In many ways I can see the comparison to Crown Center.
Crown Center is a "city within a city" that hasn't in the past lent itself to any sort of pedestrian activity outside its reaches. But, to be fair, you must think about the context of the construction (it was generally good to make drive-through developments, no respect for "old buildings"). The center was a massive mixed-use project decades before that was widely popular. However you can still see the suburbanization that went into it: huge surface lots in the back seem virtually identical to something you would find at Corporate Woods, no storefront retail. But I think some of this is changing as area around it become less blighted and more chic (Western Auto, Crossroads/Union Station). People are moving in and Crown Center will have to get used to being one part of the neighborhood rather than the neighborhood.
Do you see CC being a cohesive part of greater downtown, or will it isolate visitors from greater downtown?