Hell, even in Detroit, the real estate market is going bananas. My neighbor just sold his condo (same basic thing as mine) for well over double what I paid 2.5 years ago. It's insanity, but I think it's a good trend that so many people want to live in cities. The suburban thing can't just keep expanding to infinity. Our generation seems much happier than our parents to have walkable neighborhoods, amenities close by, and a better sense of community. I hated the suburb where I grew up (you know it--Rochester Hills, MI) for it's stale atmosphere, sterile lack of charm and parceled land plots. I'll take the crime here in Detroit if it means that I get 6 bars withing three blocks of my house, a bakery, a grocery store and small, locally owned retail shops all a short walk away (not to mention the chance to get to live in a building with 100 year old stonework adorning the facade; not gonna see that in the burbs).
Unfortunately, the suburbs are still expanding. Urban areas and suburbs both are. It's rural areas that are declining in raw population in many places. This is a wonderful map. Cities are much more efficient when it comes to almost anything. Waste, transportation, infrastructure... The growing demand for urban living is certainly positive, but the burbs aren't dead yet.