In case you’re out of the loop, The Sims Team has announced a new project where the entire simming community gets to be involved by voting a new theme, items, clothing and more for a new Stuff Pack throughout this year! This project will last for almost the entire rest of this year as explained in the breakdown of this Stuff Pack’s development process (the last step is voting for the Stuff Pack’s title which will take place sometime this fall).
In TheSims.com’s FAQ page about this project, the team stated that this community-involved Stuff Pack will be available in 2018:
This Stuff Pack will be available for purchase in the next year, when development has been completed.
So yeah, other than SimGurus’ promise that 2017 will be a great year for The Sims 4, we now also know that 2018 as well will bring new content for The Sims 4!