Exactly, due diligence is key. I'm just a noob to this whole business, but I've already been taken by pumpers - and, hopefully, I'm in the process of learning how to recognize when I'm being taken, at least some of the time.
Empty promises, lots of predictions without proof, happy positivity, nobody backing anything up with data, angry responses to comparing a stock to similar companies, ostracism of anyone posting realistic criticism of a company's future - those seem to be warning signs that one's become surrounded by pumpers.
But no matter how much the posters pump some company, it looks like all you have to do is read the company's filed documents to figure out what the company's real promise is. Plus, reading sedar filings is educational, and learnin' is fun!
(Of course, a mining company could defraud you directly, and there'll be no way of knowing you're being taken until too late.)
I have learned: trust no one on the internet (I mean, they teach that to 5 year olds). No amount of research is too much. Don't make a move if you haven't been given enough data to quantify the downside. Keep begging people "prove to me that my assumptions are wrong". Give everyone their 5 minutes to convince you, and then analyze what they wrote to see if they've presented ANY proof to back up their claims.