It’s a pretty neat concept. Apparently Google acquired Grand Central last year. The idea behind it is to have a single number that when called can be diverted to any other number from a group of numbers depending on the caller. This includes being able to mark different numbers as spam and diverting certain calls to a disconnected number message.
It’s currently in beta still, and the beta is only open to US users, but the idea sounds great, I can see it being really useful. It may be a bit problematic initially, but the ability to treat phone numbers like emails would be great! What do you think?