I'm looking into advanced distros (like arch) and slackware is fascinating. Is it still supported/used? If you'd like to comment an alternative distro, please do.
As much as I Iike and respect Slackware and Patrick Volkerding, I would go with Arch if I were you. According to the change logs, the last commit was June 23rd of this year. Arch is more actively worked on and developed. I learned Linux on Slackware so I will always be partial to it, just like I learned Unix on OpenBSD and will be partial to it as well. But for me, Arch is the way to go for Linux. Arch's wiki is fantastic.
Not sure which change logs you're looking at, but both stable and current were updated yesterday. Current is most days, stable is usually a couple of security patches and bug fixes a week.