My reaction on the bank scams is...really? You're STILL trying this one? They're so ludicrous, I've always felt anyone falling for them has to bear a large share of the responsibility. Mind, there's some better ones that take a different tack, but the whole "please help me transfer $18m" or "you are the designated beneficiary of $9m" from someone you don't know...from a foreign country? Please.
Couple of hints. Best practice is to NEVER click a link. Open up a new browser window and connect to the site through the normal route, if you think it's legit. Check return addresses. If it's supposed to be from PayPal, the return address should clearly parse to that. An exception may be, for a smaller business, that they're using Constant Contact; that'll show, and the address will point to Constant Contact, probably. But if it's some bizarre string to some crazy server? It's fake. Similarly, let your mouse hover over links, but be careful not to click. You should see the actual link show in a popup. Same things apply here...is it going where it should?
As far as private messages here? If it's not a private note, or a direct response to a buy or sell post...start by assuming it's fake. I seriously doubt that's being paranoid; and for darn sure, better safe than sorry.