~saintsrow.wikia

The game was confirmed to be in development prior to Saints Row: The Third's release; THQ's Danny Bilson briefly said in an interview with X-Play on November 9, 2011, "I already know what Saints Row 4 is about, and it is wilder than [Saints Row: The Third]".
It was confirmed to be in development for PC, PlayStation 3, and Xbox 360 on May 16, 2012, via the LinkedIn profile of a Volition, Inc. developer.

On June 11, 2012, the new THQ president, Jason Rubin, was quoted as having expressed his distaste over Saints Row: The Third's "tone and crass humor", and noted his intention to change that in future entries. Rubin believed that the game's presentation limited its potential audience, when it could have striven to be the next "Red Dead Redemption or Skyrim" (referring to the two games' critical and commercial successes). Rubin further allegedly stated that Saints Row: The Third was a product of "the environment at the time", and that he aims to change that. Rubin later claimed on Twitter that he had been misquoted, and that it was in fact the interviewer who was embarrassed.

A few days later, on June 20, 2012, Rubin stated that the Saints Row: The Third standalone expansion, Enter The Dominatrix, had been cancelled and instead would be merged with "The Next Great Sequel in the Saints Row Franchise", allowing the team "more time, more resources, and a broader scope for the project". He also confirmed the game was scheduled for a calendar 2013 release window.

Following THQ's filing for bankruptcy and subsequent closure, the Saints Row franchise along with developer, Volition, Inc., were auctioned off to Koch Media for $22.3 million on January 23, 2013.

Independent game development company High Voltage Software (developer of the Wii video game The Conduit) are helping out with art assets for the game.

Christ Stockman tweeted on Feburary 4th that there is a rough release date of August and the CEO of Koch Media, Klemens Kundratitz, confirmed that the game will be released in 2013.

Deep Silver stated that they had left Volition, Inc. in full creative control of the "long-in-development" game, with "additional time for polishing".

The game will be showcased at PAX East 2013 in some capacity.