there's other message boards I'm on that sort of do this, but not 1-topic, but a topic every week (52 every year approx).
The Calendar topic is good, but maybe it's best for anticipation as opposed Now Available/Released.
Maybe it should also be a stickie?
also there are some releases (including singles) that do not get released on Fridays still (I'm thinking of Bandcamp releases and Album Release Shows from local artists namely). In other words, it's fine to mention something that is released THAT WEEK for example.