Called Comcast this morning. If all goes according to plan, everything will get shifted over to Comcast XFinity on Wed. August 7th. We are still trying to sort out a glitch involving our current home phone number, so if that stops working for you about then, you'll know what happened. :)
And then it will be time to talk to AT&T, DirecTV, and ADT, as we will no longer be requiring their services.