Regarding the forum and those out there running similar websites, I think we all agree Bitcointalk is ahead by a long distance but (and I know some will disagree) in my opinion, other forums will increase in traffic and prominence over time because of the mixer ban. Mentioning those forums should be allowed without prejudice and in those forums they should also allow the mentioning of other forums too.
I guess Altcoinstalks holds the 2nd place in terms of visitors and activity on the clear net. It's obvious that some of us do not care about the darknet forums which could be more crowded, but I am not aware of any because I am not regular there. Even altcoinstalks admin agrees that Bitcointalk is the top forum website and they don't think they are here to complete with Bitcointalk.
I do not think any of the forum owners think that they would be able to beat Bitcointalk in terms of monthly visits and the activity. But, yeah, all of them try to get some visitors from Bitcointalk because they know how huge the number of users of Bitcointalk.