It seems to me that anytime there is someone pumping the stock the next day or week or so, the stock takes a big ol' dump. I know there must be some honest writers there, but all the fake pumpers just ruin the site. I have to read the whole article and then do my own due diligence to figure out whether he's full of it or not. But then why even bother reading the article at all? You expect that sort of nonsense on the yahoo boards, but that's just a message board with very little in terms of moderation or oversight. But I would think that the mods would rein in penny stock pumpers and the like on sites like fool or seekingalpha.
I can't speak for Fool but SA has some pretty good contributors. I'm sure there are some duds as well. Over time you develop a feeling for who has a handle on things and you can follow them.
Ultimately you want to rely on your own brain. There is just too much conflict of interest in this business that does not get disclosed. And other shenanigans of this sort.
It's on a lot of front-end newsfeeds and it's absurd. Some asshat with an opinion and it comes across as a wire-story? SA -> blocked.