Twitter is kicking into motion one of the most anticipated initial public offerings in the tech industry since Facebook. The popular microblogging service yesterday announced – via a Tweet, no less – that it has confidentially submitted an S-1 to the SEC for a planned IPO. Details are still scarce on how many shares of the company will be offered, the timing of the offering and the price of the shares.

Company executives had long dodged questions about going public, claiming they were more focused on the long term and creating lasting value than near term optimization of revenue. The Guardian speculates it is likely that Twitter was forced to file for an IPO because it had enough private investors that regulations required it. Under the Jobs Act a company in the US has to go public if it has more than 2,000 private investors.

This Act, which stands for Jumpstart Our Business Startups and became law in 2012, also provides a vague hint at Twitter's revenue, as only companies with less than $1 billion in annual revenue are allowed to file IPO plans confidentially and keep financial data under wraps until three weeks before marketing its stock in a "road show". The road show is one of the final steps in the IPO process, in which the company gives presentations to potential investors, and is typically followed by pricing of the shares and the first day of trading.

For what it's worth, the service is known to have over 200 million active users and is believed to have generated more than $100 million in revenue in the final quarter of 2012. Twitter makes its money primarily by selling ads, and is increasingly becoming an attractive venue for advertisers due to its timeliness and topicality, with people actively tweeting alongside specific events such as TV shows, concerts, and breaking news. According to eMarketer, Twitter will rake in in $583 million in advertising revenue for 2013 and hit $1 billion in 2014.

Twitter is currently believed to be worth between $10 billion to $20 billion. That's a far cry from Facebook's $100 billion valuation last year, but going public at this stage leaves them more room to run up revenue and valuation, which is very important when it comes to Wall Street. The timing is also noteworthy as investors are recovering confidence in mobile and social, with Facebook's shares hitting a record high this week at $44.75.