The Prisoner remake got off to a disappointing start on Saturday for ITV1, despite a lead-in from the premiere of Britain's Got Talent. Airing at 9.30pm, the AMC/ITV co-production attracted just 3.209 million viewers, losing 7 million of BGT's peak audience. This is perhaps understandable, as the majority of BGT's fanbase aren't going to be interested in a sci-fi remake of a '60s cult classic, and it's debatable that the average ITV viewer would find The Prisoner appealing. I guess the 3m who did watch were strictly sci-fi/Prisoner fans? It'll be interesting to see how many of the 3m tune in for episode 2.
Earlier that same evening over on BBC1, Doctor Who's "Victory Of The Daleks" attracted 6.227 million viewers, although that overnight figure's likely to rise when HD, PVR, VOD, and iPlayer stats are taken into account. For example, last week's "The Beast Below" had 7.93m BBC1 viewers, but the total figure was adjusted by BARB to 8.42m when they factored in other viewing methods throughout the week.
Also, if you're interested in comparing Steven Moffat's era to Russell T. Davies', the overnight figures for series 4's third episode, "Planet Of The Ood", were 7.5m. David Tennant's third ever episode, "School Reunion", attracted 8.3m viewers back in 2006.