Right now, it's unclear just what the photo-sharing social network will announce. Speculation has ranged from a photo-printing service -- based on the odd form of the invites -- to a private messaging service that could rival Snapchat and WhatsApp.
We may not know all the details now, but our live blog will bring you the news right as it happens.
In the three years since it launched, Instagram has grown tremendously. The social network says it now has 150 million active users worldwide. Last month, the service -- which sold itself to Facebook for $1 billion last year -- announced that it was starting to run advertisements in an effort to monetize its business.
Last week, CNET received a mysterious invite -- sent via FedEx, not e-mail -- for an event to "share a moment with Kevin Systrom and the Instagram team." The package, wrapped with brown paper and a white ribbon, contained a wooden block, 4 inches long and wide and 1.75 inches thick, covered with a printed Instagram shot and a slot in the back so it can be hung on the wall.
A spokeswoman at the time declined to provide further details about the event, but recent press reports have suggested that the photo-sharing social network is gearing up to introduce a private messaging service within its photo and video app. It also reportedly has been experimenting with group messaging. However, the format of the invite itself seems to suggest a different kind of announcement, such as a service that would allow users to print their photos.