I’m typing this post while connected to my Time Capsule router. You’d never know that from looking at the Airport Utility, which can’t identify the router on the network. Never run into this problem before updating to Snow Lion.
Fun aside: last night my MBP couldn’t find its backup images on the router. The ‘solution’ was to delete the existing image bundle on the Time Capsule - I could navigate to them in Finder - and then OSX could see the Time Capsule and backup to it.