Public forums is one of the best place to get opinions of others using a particular site so we can get the honest review instead of paid one by reviewing websites then we also have to take a look at how long they have been in the business and how they execute the big withdrawals which is basic enough to identify and trust an online casino in my opinion.
Which forums are you talking about? Bitcointalk where most of users of the gambling section are just there for the quotas of their signature campaign, mostly licking boots of any casino around? I don't think it's more reliable than a serious reviewing website where review from users are available.
Not just talking about the bitcointalk alone, just anywhere people are allowed to express their own experience it either can be a social media or just random article and all those stuffs collectively will help us to find shady ones for sure. Well about bitcointalk we may not find all the post made contain some information but we have some system like DT which helps us to identify the scammers if they attempted or did any shady activities.