Sheryl Sandberg, billionaire Chief Operating Officer of Facebook, has received mixed reviews for her new book "Lean In: Women, Work, and the Will to Lead."

Touted by some as a contemporary Feminist Manifesto, Sandberg's book encourages women to be more assertive in the workplace.

The Facebook executive's writing career was springboarded by her 2010 speech for TEDWomen, an arm of the annual TED conference, a nonprofit devoted to Ideas Worth Spreading.

Her speech, entitled "Why We Have Too Few Women Leaders," has been viewed more than 2 million times on TED's website.

"Women are not making it to the top of any profession anywhere in the world," Sandberg said in the speech. "The numbers tell the story quite clearly. 190 heads of state-- nine are women. Of all the people in parliament in the world, 13 percent are women. In the corporate sector, women at the top, C-level jobs, board seat-- tops out at 15, 16 percent. The numbers have not moved since 2002 and are going in the wrong direction. And even in the non-profit world, a world we sometimes think of as being led by more women, women at the top: 20 percent."

In "Lean In: Women, Work, and the Will to Lead," Sandberg writes that she is speaking to "any woman who wants to increase her chances of making it to the top of her field [to] pursue any goal vigorously."

She tells working women to stop allowing self imposed stigmas to "hold ourselves back in ways both big and small."

The Facebook COO believes women should negotiate higher salaries, assume "a high-power pose", and pursue leadership positions.

Yet not everyone is jumping onboard the Sheryl Sandberg bandwagon.

"Sandberg barely mentions the millions of single mothers in the workplace," Connie Schultz, columnist for Creators Syndicate wrote. "She does, however, advise women on how to find a supportive spouse-- who, in her book, is almost always male. Ambitious lesbians will have to find their tutorial elsewhere."

Boston Globe columnist Lauren Stiller Rikleen agrees.

"As someone who spends much of my professional life focusing on women's leadership and advancement, I love Sandberg's thoughtful advice to women," Rikleen writes.  "My hope, however, is that she will use her considerable platform to address the workplace norms and practices that are more of an impediment than our own fears and inhibitions."