These are websites that have KiCad content. They may or may not have forums but can still be very helpful.
Submit a pull-request to the kicad website repository as long as you meet the following conditions:
Your site must be open and cannot charge for access
You do not misrepresent yourself as being an official KiCad entity
There is a primary focus on KiCad content. i.e. your personal blog that has some KiCad related posts is not valid, a forum dedicated to KiCad or a blog only with kicad posts does
You accept your site can be removed from listing at any time at the discretion of the KiCad website maintainers