Yes, but it [currently] also says this:
"Memrise has been designed to help you connect every new word in the densest, most vivid fashion possible. We do this with mems. Mems is our natty word for the morsels of interesting and relevant information you see beneath every word on Memrise. Mems can be mnemonics, etymologies, amusing videos, photos, example sentences: anything which helps connect what you’re learning and bring it to life. Memrise is a wonderful community of mem-makers: we believe that there’s no idea or fact that isn’t made easier to learn with a choice mem.
“Mems work best when they stimulate your senses, imagination and your emotions. The memories that result from such processing last longer, stand out better are just plain enjoyable and satisfying to recall.”
and:
“We believe that every learner is partly a teacher, and we hope that once you get started, you’ll soon be supplying little nuggets of wit and wisdom to help the rest of the community as they learn!”
and:
"Millions of people have learned what you want to learn. That’s why on Memrise we’re collecting all the most effective ways people have found of remembering all the most interesting information.
"As you learn, you share your ideas to help others, just as you benefit all the time from the ideas other people have shared.
“This way, we all learn quicker and more effortlessly. Memrise is the creative community for those who share the joy of learning.”
I expect this will get changed. As you say, the Release Note talked of “selected” mems being shown in future, but I can’t see them spending much, if any, time selecting mems from user-created courses. Also, as we know, what works as a mem for one person doesn’t work for everyone.
As I and others have said before, this change is driven more by server capacity and ‘housekeeping’ issues than anything else.