The SIPM community platform is still running and if you notice, it doesn't have ads running all over and run on its own merits.
It's meant to be a platform that helps connect newbies in project management with the experts. As far as I know it's one of a kind. It's FREE. Word spreads just by word of mouth and if you like it, let your friend know.
Recently there's been too many of fake sign ups and I think it's wrong on the part of those who are doing it. Please understand the site was build as a way to give back to the project management community and allows and encourage interesting discussions, finding mentors and a way to find your next job or internship. So, if you have nothing to learn or offer, please don't malign the interest of the site and this community.