It's been rumored since November, but the New York Times reports that Facebook will file for its initial public offering tomorrow. The company is reportedly looking to earn about $5 billion in new capital by selling its stock on the open market for the first time — a number just half of the $10 billion rumors that have been floating around, but things could change "significantly" as the process gets underway.

All Things D is also reporting that Facebook's board of directors has been meeting all day ahead of the IPO filing, and that the company wants to minimize the hype and bubble-effect of what promises to be the most significant public debut of any company in years. (To put it in context, even a $5 billion offering would put Facebook within striking distance of the biggest IPO in history — Infineon Technology's $5.23 billion debut in 1999.) We'll be tracking this one closely, so stay tuned.