There are certain segments of fandom where the greatest version of the BBC's Doctor Who is obviously the last actor who played the part. But the raw numbers in America have good things to say about current iteration Peter Capaldi.
The Wrap has the latest ratings report for the first season of the 12th Doctor, the series earned its highest ever ratings on cable channel BBC America. The DVR-considering Live + 3 Day ratings averaged 2.035 million viewers across the first season, and the show continued to grow this holiday season as the Christmas Day special for 2014 earned 2.312 million viewers day of on its way to 2.616 million. Of course, these numbers run far behind the show's ratings in the UK where Doctor Who is essentially a national institution and brings in from 5 to 7 million viewers each week.
This bodes well for the future of the Doctor in America, and fans can already look forward to one more year of Capaldi pairing with current companion Clara played by Jenna Coleman.