I haven't worked out all of the details out, just a heads up that I'll be doing a meetup and you'll need to be a Chicago Architecture Foundation member. The reason for this is that we will be going to buildings only open to members and we will have VIP passes that allow for skipping the lines at other buildings.
I bought a membership today at their store at 224 S. Michigan and received my VIP pass on the spot. You can also do it on their website and use the confirmation email as your VIP pass. In either case you need a photo ID. A standard membership is $65 for a year, there are a lot of other benefits besides the open house. Their website is http://www.architecture.org
I'm thinking right now we will met at the Jewelers Building on Wacker Drive and Michigan as it is a member only building this year.