I wonder if they'll choose to make a whole diverse city or just a "monoculture" of 20 somethign roommates. ? I dont imagine seniors are usually attracted to Campus' main market (see the communities on their website). But cities usually have all sorts of demographics.
I imagine these communities will end up resembling the student ghettos of Allston, MA. An amazing place when you're 18, but just depressing when you're 28.
Reminds me of how 'The Real World' TV show started out as a whole bunch of different people living together in SF then as the show progressed season after season it just became a 20 something mono culture.
Maybe as they develop and become bigger... But kids out of uni are more or less still 'getting away' from the adults. And empty-nesters probably would have a different tolerance for noise and active hours.