Oh, that's right. I'd totally forgotten about it.
https://slashdot.org/faq/friends.shtml
I stopped reading it when I couldn't find interesting articles [EDIT: 0]. I think the firehose style of HN or Reddit is, in many ways, better than the curated submission system of /.. User directed submission moderation + scanning /new is usually enough for me, paired with going to direct to certain news sources (for whatever particular topic or category).
The comments were also pretty annoying. For those not familiar: See the strong anti-Microsoft posts that periodically show up here, and imagine that as the only thing that makes it to +5 when MS announces something. A ton of rhetoric with no substance.
EDIT:
[0] There were interesting articles. But there was a period (not sure about today) where the updates to the frontpage were incredibly slow. Perhaps I could've dug more into the topic areas or set some different display options, but things changed too slowly and I'd end up seeing the same articles for most of a day, or days.
On the one hand, this is a good format for some sites (and maybe for /.) as it allows things to remain visible for extended periods. On the other hand, it wasn't good for my usecase. /. was an aggregator, I wanted to see it update frequently. If I wanted a news magazine that totally cycles its front page only once a week, I'd be on that site.