I have already questioned the messages that appear under the topic that appears randomly by creating a topic in Bitcoin Discussion so that I find the answer that the message that often appears under the topic is factoids.
The message that appeared was apparently the advertisement shared by the forum admin.

You can deactivate advertisements so as not to be displayed again by installing a plugin to make an advertisement not displayed again. Settings on the Bitcouningk account profile are also available. This is all I found in the local discussion room shared by experienced members.

The messages are quite entertaining and useful.

Regarding Bitcoin is still a beta software, I can't answer because I don't know about Bitcoin in detail.