This takes the adage of "put your money where your mouth is" to new levels.

In an open letter to newborn daughter, Max, posted online Tuesday, Facebook co-founder and CEO Mark Zuckerberg, and wife Priscilla Chan announced that they'll be giving 99 percent of their Facebook shares to charity over the span of their lives. Those holdings are currently worth $45 billion.

"As you begin the next generation of the Chan Zuckerberg family, we also begin the Chan Zuckerberg Initiative to join people across the world to advance human potential and promote equality for all children in the next generation," the couple wrote to their newborn daughter, Maxima Chan Zuckerberg, in the letter posted on Facebook on Tuesday. "Our initial areas of focus will be personalized learning, curing disease, connecting people and building strong communities."

The announcement has already received over 250,000 "likes" — and rapidly counting — as of Tuesday evening, including those from Arianna Huffington and Melinda Gates.

Although they promise to "share more details in the coming months" once they "return from our maternity and paternity leaves," curing disease, advancing human potential and promoting equality are areas that the couple especially feel strong about.

Within their open letter, they pinpoint heart disease, cancer, stroke, neurodegenerative and infectious diseases as the five leading causes of death and cite an acceleration in technology as society's best shot at preventing — or better yet, eliminating — them in the future.

Their ideas of advancing human potential plans on pushing the envelope on how great and long a human life can be, while their promoting equality concept attempts to broaden access to opportunities regardless of one's location or family background.

Can't wait to hear more details about their Initiative in the new year.