Hitting the 100 million member milestone is the latest move in an interesting year for the social network.

For instance, the company earlier this year with the Securities and Exchange Commission for an initial public offering.

Despite its role as a second-tier player in a social networking world that includes far more widely-used Facebook and , LinkedIn may be the first one out of the .

For now, LinkedIn is celebrating its 100 million members. And they're doing it with some interesting stats about the site and its members.

A full 100% of Fortune 500 companies have executives on LinkedIn. Ebay, Amazon.com and Cisco are among the most represented companies.