Also featuring mother and daughter Sue and Beryl Vertue - producer and executive producer of the hugely successful TV series Sherlock, the list recognises screenwriters Abi Morgan and Heidi Thomas, who adapted period pieces Cranford and Call The Midwife.
Broadcaster Emma Freud nominated the Strictly Come Dancing host for being "a hugely clever Cambridge graduate masquerading as a TV bunny".
"She has a massive heart and knows how unimportant her work is, which is why she is so important in TV," she added.
Panellists who helped to compile the power list included Woman's Hour host Jenni Murray and Pointless co-presenter Richard Osman.
Copyright Speakers Corner 2017