According to "Reminiscences of a stock operator" it is not illegal to make false positive statements. It is (was?) illegal to make false negative statements presented as material fact. However as long as it is clear that you are stating an opinion and not representing it as a material fact, you can say whatever you like, positive or negative. Regardless of whether the law has changed since early twentieth century, there is weak enforcement. Wall Street has always depended on lying, cheating, and stealing. Trash and buy is just as prevalent as pump and dump. Both GS and Barrons buddies, and their ilk, are masterful practitioners of both pump and dump and trash and buy. I mean, why do you suppose investment banks hire analysts?
Much of wall street is close to obsolete in terms of any productive value. At this point wall street is what, 95% rent seeking? http://en.wikipedia.org/wiki/Rent_seeking