On one of the threads in the gambling section someone asked about investing 100 btc, to what I replied with what most would consider a very reasonable advise. Within literally 30 or 40 seconds, my reply was deleted. I believe allowing this is extremely harmful and misleadings readers towards believe they are viewing a balanced discussion, but little known to them it is tightly censored. This is especially dangerous when it comes to things like other sites and services.

As a form of spam protection, I would support the ability of self-moderated thread creators to minimise-by-default someones reply -- but allowing outright deletion seems like a very harmful policy.