Just got a TiVo HD up and running today on Comcast in the SF Bay Area. Great experience all around. I called Comcast last week to order the cards, and was told to simply go to my local office. The TiVo arrived yesterday, so I went over to the Berkeley Comcast office first thing this morning -- only to find out they had no cards in stock! But the very friendly Berkeley rep called the very friendly El Cerrito rep, and found two single-tuner cards for me. Zipped over to El Cerrito, picked them up, and came home. Installed the cards in the TiVo, and called the number shown on the CableCARD display. Told the Rep I needed to activate my cards, she put me on hold for about 5 minutes, and bingo, HD TV! I told her everything was working, and we hung up -- my only mistake, as I realized about 20 minutes later my premium channels (HBO) were not authorized. But turned out to be no big deal at all: another call, another friendly rep (who this time asked for my Host & Data info!), another 5 minutes on hold, and this time I was told that she saw a problem, and would do something (she was quite vague) and HBO should be available in about 20 minutes. Which it was! Whole thing couldn't have been easier.