The BBC has appointed Alan Yentob as controller of BBC1, the pubcaster’s mass audience TV channel. Yentob was formerly controller of the more specialized BBC2.He replaces Jonathan Powell, who resigned at the end of last year to join the new ITV station Carlton TV. Yentob’s background in arts programming makes him an unusual choice to run the BBC’s flagship entertainment service, but he has attracted widespread admiration inside and outside the pubcaster for his performance at BBC2, where he increased ratings and won critical plaudits. BBC1, by contrast, has struggled in the past couple of years to win much approval from audiences or critics. Ratings have declined as the channel has tried and failed to compete head-on with commercial rival ITV in mass entertainment programming.