4. Nancy Tellem

Under Tellem's steady oversight, CBS rebounded strongly from the WGA strike with a diverse slate of new projects, including one bona fide hit (drama "The Mentalist") and a rising comedy ("Worst Week"). And her group was the No. 1 supplier of primetime programming both pre- and post-strike this past season.

The former Warner Bros. Television executive, who joined CBS in 1997, says she likes to "zig where others zag," which has led to her longstanding reputation as a tenacious leader and tastemaker. To that end, she's taken the lead in keeping costs down with co-productions like the Canadian pilot "Flashpoint."

Outside work, Tellem devotes charitable attention to Seeds of Peace, which unites Palestinian and Israeli children at a sleepaway camp in Maine. Of her future agenda, she adds, "At some point, I'd love to figure out an environmentally friendly business that had nothing to do with entertainment."