I read general_ai's comments. I don't think your summary's fair and submit that your tone's a little aggressive.
This doesn't get things back on topic. Though, it took minimal effort to find instances of Salon running ridiculous reports. [0]
Here the real problem: these companies can't get their hands on content fast enough. WaPo produces 500 articles/day and 1200 items/day. AFAIK, because there's no real punishment for quasi-spurious claims, there's no incentive to spend marginal time vetting sources. Today, the story can be shared 100K times in the time a retraction takes place. But by then, the damage has been done, and again, the punishment isn't material. I don't think a retraction fully undoes the damage of spurious reporting.
[0] http://www.slate.com/blogs/the_slatest/2013/01/23/salon_trut...