I read that the decision would probably be made in 2021. The idea is basically pushed by one sports manager (Michael Mronz) and the idea is to have 13 cities host the olympics together. For example:
Aachen = Equestrian, modern pentathlon
Bonn = Baseball, basketball, softball, archery
Dortmund = Football, shooting, wrestling, road cycling, skateboarding
Duisburg = Football, canoeing, rowing
Düsseldorf = Basketball, badminton, track cycling, beach volleyball, handball, judo, tennis, table tennis, volleyball
+ Essen, Gelsenkirchen, Cologne, Krefeld, Leverkusen, Mönchengladbach, Oberhausen, Recklinghausen
Here you can find a map, which sports should take place where (according to first plans):
http://www.wz.de/home/sport/olympia-in-nrw-diese-staedte-sollen-die-spiele-2032-ausrichten-1.2474742
I think people could get behind it, but the whole idea is to keep it very cheap, so we know what the IOC will think about it ...
The people who organized this said that 80% of the facilities are already there and have to be renovated, there are 5 stadiums with a capacity of at least 45.000 and 24 indoor facilities with a capacity of at least 3000. All the swimming competitions should take place in a temporary pool inside the Veltins Arena in Gelsenkirchen.