The only concern is that Facebook is, well, growing. One reviewer claiming to be a software engineer warned, "Keep the hacker culture, beware process and corporate behavior."
Other CEOs receiving top ratings include SAP's co-chief executives Bill McDermott and Jim Hagemann Snabe (99 percent), McKinsey & Company's Dominic Barton (97 percent), Ernst & Young's Jim Turley (96 percent), and Northwestern Mutual's John E. Schlifske (96 percent).
(Read More: America's Best Dressed CEOs)
Big movers include Amazon.com's Jeff Bezos, who moved up 13 positions to 16th place, with a 93 percent approval rating. However, Wall Street titans lost some ground this year.Goldman Sachs CEO Lloyd Blankfein has fallen from 11th place to 36th, and JPMorgan Chase's Jamie Dimon is down from 14th place to 33rd.
What about the women?
The only woman to make the top 50 list this year is Sharen Turney, CEO for Victoria's Secret, a subsidiary of Limited Brands. She came in 42nd place with an 82 percent approval rating, one slot above Secretary of the Navy Ray Mabus.
(Read More: And the Best Place to Work in 2013 Is...?)
As for the other female CEOs in corporate America, it's a mixed picture. Meg Whitman of Hewlett-Packard made the top 50 list last year, but fell off this year with a 79 percent approval rating. PepsiCo's Indra Nooyi has a 69 percent rating, and Xerox's Ursula Burns has only a 26 percent approval rating. Ouch. Lockheed Martin's new CEO, Marilyn Hewson, earned an 82 percent approval rating already, but she is too new to qualify for this year's list.
Same for Marissa Mayer. The Yahoo CEO has been stirring up the pot with her attempts to change the corporate culture at the struggling web company, but Mayer has seen her approval rating inch up. It currently stands at 87 percent, much better than her predecessors—Scott Thompson (48 percent), Carol Bartz (54 percent) and Jerry Yang (43 percent).
Mayer's moves to stop to telecommuting and raising the bar on hiring standards seems to be winning over most employees reviewing her on Glassdoor.
(Read More: Yahoo's Mayer Gets Internal Flak for More Rigorous Hiring)
One Yahoo "software engineer" wrote, "Morale has had its ups and downs with every new CEO, but I think Marisa knows what she is doing and everyone seems to have gotten a morale boost with her on board." Another added, "Yahoo needed someone to make tough choices, update the culture and technology, and focus on products again, and that's what she's doing."
It will be interesting to see what they say a year from now.
—By CNBC's Jane Wells; Follow her on Twitter: @janewells