I've noticed that since DreamHost have done this, there has been a large increase in forum traffic, which I think we'd all agree is a good thing. However, with this increase in traffic has (seemingly) come a corresponding increase in the type of posts that you mention.
What to do about them? Of-course, DreamHost could just delete them as they find them, but in the past they have shown a reluctance to delete such critical posts without good reason, perhaps to avoid any claims of censorship and the like.
I'm not sure we need to do anything really. As you say, if we do not reply to the obvious ones, the extra traffic/postings on the forum these days will tend to bury them fairly quickly. I am just a little concerned that seeing such posts un-responded to could sow the seed of doubt in a potential customers mind, especially when the post contains obviously false information, well obvious to existing customers anyway.
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