Facebook Inc (NASDAQ:FB) Director of Product, Blake Ross, has announced that he’s leaving the company. The news, which was first broken by Tech Crunch, is sourced from a statement he posted on his Facebook profile page earlier today. The executive’s Facebook page can be found here.

Blake Ross

The software developer, who is most well known for his work on the Mozilla Firefox Web Browser, joined Facebook in its first ever acquisition, that of Parakey in 2007. Parakey was working on a web operating system when it was acquired. Ross will actually leave the company next month, but announced his departure today.

Ross joined Facebook Inc (NASDAQ:FB), along with another Parakey and Firefox veteran Joe Hewitt, when that company was acquired by the social networking giant. Hewitt left the company in May of 2011. The pair worked on much of Facebook’s mobile offering, including its iOS applications.

The loss of the executive is likely to be felt sorely in Menlo Park, but it may have an even greater effect on the firm’s stock price next Monday. Facebook investors have been jittery since the firm’s disastrous IPO last May. It doesn’t take much to make them question the company’s future. The departure of one of the firm’s key executives might just be enough to set them off.

The announcement of the departure, which came on Friday evening as the market was about to close, is hardly a coincidence either. It allows investors time to reflect on the departure of the executive before they decide whether or not the move hurts the tech company. By Monday morning this will be old news, or at least that’s what some of the company’s investors will be hoping.

The message that Ross posted on his page was lighthearted and magnanimous. The full statement is printed at the end of this article. Highlights included the executive’s sarcastic assertion that he’d decided to leave the company because a Forbes’ writer’s kid told them Facebook Inc (NASDAQ:FB) wasn’t cool any more.

Ross admits that he’s spent “half my life building software in a 10-mile area of Northern California.” He thinks it’s time for a change and for him to find out what else is out there. Ross began working in Silicon Valley at 14, when he took a job at Netscape. The statement ends with hear felt thanks.

Hey everyone, I’ve decided to leave Facebook. I’m so grateful that I’ve had the opportunity to learn from and grow with you.

I’m leaving because a Forbes writer asked his son’s best friend Todd if Facebook was still cool and the friend said no, and plus none of HIS friends think so either, even Leila who used to love it, and this journalism made me reconsider the long-term viability of the company.

Also because, after scaling a website in a dorm room to a platform connecting a billion people in 196 countries through revolutionary high-efficiency auto-cooling datacenters, you guys will probably never figure out how to sell a Quiznos turkey club on a phone.

In all seriousness, even after switching to part-time at Facebook, it’s just time for me to try new things. I was 14 when I came to the Bay Area to work at Netscape (socially stunted badge pic below). That’s half my life building software in a 10-mile area of Northern California—a rather long stretch considering I spent the first half of my life learning disciplines as varied as standing up, eating, and getting Bar Mitzvahed.

My parting advice: Cherish the launch days. To be surrounded by such bright people, brimming with optimism, forgetting to eat, is a blessing. It’s the kind of manic hopefulness that adulthood is supposed to drain out of you, and I will miss it most.

Launch day is also a great day for Legal to find out what you’re launching.

Guys, thanks for everything. You’ve all brought a lot of joy to this stone cold heart.”