(Perhaps surprisingly) Facebook - I'm in a few AI/ML/DL related groups, and there's one individual in particular who does a really good job of identifying interesting new papers and articles that show up and then submits the links or one or more of those groups.
Google News - mostly popsci articles show up here, but a few are of interest now and then.
HN - A few really interesting AI related links show up here from time to time.
/r/machinelearning on reddit
/r/artificial on reddit
Manually browsing ArXiv, JMLR, JAIR, and a handful of similar sites.
Email newsletters - I am subscribed to a few newsletters that surface interesting items
Youtube - some conferences put all (or most, or some) of their presentations up on Youtube. The AGI conference, for example, usually has their presentations there. NeurIPS also posts a lot (if not all) of their sessions. And so on...