Updated 11/14: Earlier this year, a PC version of Sunset Overdrive was listed on the Korean Game Ratings Board, but new evidence has recently appeared pointing to a PC port coming later this week.
Twitter user @Wario64 posted evidence of an Amazon link (which has since been removed) to a PC listing of the game with all of its DLC included, available to preorder for a November 16 release at $20 USD. On top of this, a Steam database page for the game exists which clearly features promotional art for Sunset Overdrive, and an ESRB page listing a Windows PC version of the game went live last week.
Source: IGN.com Update: More Evidence Points to a Sunset Overdrive PC Release