[ssmoot]

I could be wrong, but I'm not sure how else they'd be showing up in my library under "Recently Added" then. I didn't specifically create any new playlists or anything and it's just the songs I "hearted".

I assumed it was just a "genius" thing at first as well, but there they are. Maybe it's new.

[parasubvert]

I had thought the "plus" button actually did the adding instead of "heart" which was more algorithm food. But I haven't dug around enough maybe?