I recently had a bad experience with moving and transferring my Comcast TV/Internet to my new apartment. I gathered from your TV ads that is would be a simple phone call to have my cable and internet service transferred since I own my own modem, my cable box is only 1 year old and I was moving to another apartment in the same complex.
I called customer support and was told that I needed to return my cable box and pick up a new one because each box is coded for the specific apartment. This seemed odd, but I gathered the rep knew was he was doing. He said he would transfer my internet (since I use my own modem) and set up an appointment for me to pick up my new box on 10/30 between 5:00-5:15.
When I arrived at the comcast store on 10/30 (around 5:10) I was told there was an issue with the computer scheduling and I'd have to wait about 10 minutes. 30 minutes later I was finally waited on and told there was no reason for me to return the box, the rep on the phone could have transferred the TV service. Also the internet was not transferred and had to be done in store.
Comcast makes their moving process seem incredibly simple, but in reality when the customer service reps in charge of transferring service over the phone are either too lazy or inexperienced to do what is expected it drastically complications what you make out to be the least stressful part of moving.