Facebook said today it has hit 500 million members, a milestone that had been anticipated by the social media industry for months.

“I want to thank you for being part of making Facebook what it is today and for spreading it around the world,” co-founder and Chief Executive Officer Mark Zuckerberg said in a blog post.

To mark the occasion, the social networking site is launching an application called Facebook Stories, which will let users share anecdotes about how the platform has made an impact on their lives.

Facebook’s membership milestone also coincides with the recent release of a new trailer for “The Social Network,” a film about Zuckerberg and the origins of Facebook that is scheduled to be released at the beginning of October.

The movie, which is written by Aaron Sorkin and directed by David Fincher, is based on a book by Ben Mezrich and focuses on Facebook’s genesis during Zuckerberg’s undergraduate days at Harvard — and the people he reportedly alienated or hurt on his way to Silicon Valley super-stardom.

The creators of the film’s trailer appear to have anticipated the half-billion milestone as well. The tagline of the trailer reads: “You don’t get to 500 million friends … without making a few enemies.”

According to research firm eMarketer, 127 million Americans are social network users, meaning they use a site at least once a month. This figure is expected to rise to 140.2 million people next year and 164.9 million people in 2014.