It's already been confirmed that the promos will likely be special locations, which means they may or may not be included in any particular game. I'd guess they count as two colors for cards like Restaurant. Do they count as two locations for purposes of Life Support Systems?
Each of them is a single location - it just has 2 types. For example the Alien Museum is both Recreational and Diplomatic. Since cards like the Restaurant and the Opera count types, they would count 2. Life Support though counts locations so it would count as one.
How did you choose the color pairs, and do they seem on balance with other 3-cost buildings?
You 'll see that the pairs actually form a circle. You have:
Business / Recreational
Recreational / Diplomatic
Diplomatic / Administrational
Administrational / Military
Military / Business
And as for the other question, yes we made sure they are on balance with other 3-cost buildings.