The days when you heard about a company’s plans for a stock market flotation via a newspaper report or a TV or radio news item are now so much part of our nostalgic reflecting on simpler, slower times with the announcement by Twitter late yesterday on its plans for such an event.

The announcement was made in a tweet.

Posted at 10pm UK time, Twitter said that it has filed Form S-1 with the US Securities and Exchange Commission as a first step on the route to an initial public offering of shares in the company.

The filing was confidential, Twitter said, so no information on what’s in the document is publicly-viewable via Twitter’s entry in the SEC’s EDGAR filings database.

That means no one can find any detail on what the company is planning, giving Twitter huge control over the story it now builds; and how, when and where it tells it, and to whom.

I saw Twitter’s tweet about fifteen minutes after it was posted. It had already been re-tweeted over 7,000 times by then and news had started appearing across the mainstream media. There’s more amplification now as you can see in the tweet itself, embedded below.

We’ve confidentially submitted an S-1 to the SEC for a planned IPO. This Tweet does not constitute an offer of any securities for sale.

— Twitter (@twitter) September 12, 2013

There’s nothing about this yet on their official blog.

Under SEC rules, Twitter now enters the so-called quiet period where the company is limited in what it can say or disclose publicly about its plans.

Cue huge speculation from anyone with an opinion and an internet connection. And jokes.

It shouldn’t surprise anyone that Twitter would use its own network and channel for such an announcement. Plus, the regulatory environment and rules on how you can make such announcements are far more relaxed now than they ever have been, where social media channels like Twitter are allowed in certain circumstances.

The communication landscape shifted again.

[Later:] The New Yorker magazine has an excellent assessment of Twitter and how it’s evolving from the broader user-experience and ad-business perspectives, focusing on developments with the Twitter service itself, the evolution of its apps and the ways in which you can use it with those apps.

A thought-provoking conclusion:

[…] what’s coming is simply Twitter following through on promises both explicit and implicit: a Twitter that is at once simpler and richer. One hopes it’s also a better Twitter.

Add that to broaden your view about the IPO and what’s next for Twitter.