I was thinking black but perhps silver would work too? I definitely want closed toe in case it's chilly (never know how cold or warm it could be in October in Chicago).

I think silver would work well.  You could also (depending on budget and willingness!) get the dyable shoes and have them dyed to match.

I checked it out and there are surprisingly a lot of non-summery silver pumps out there. Mostly they come in peep toe which are really cute!

Thanks Jellybean! Any other opinions are certainly welcomed!

what is the other color in your wedding?  i would go with that.  My BM's wore gold shoes with their red dresses and i wore red shoes with my gold dress