You remember my friend, the Demon Landlord (aka The Beast of the Borders)? It seems he's been having a bit of legal trouble with an employment agency who were wanting to charge him several thousand pounds for someone who he never employed! Fortunately, the case was thrown out of court. They then objected to his blog post on the case, (Here's the link to his blog, but you'll have to scroll down to March 19th - I can't get a link to the actual post for some reason) and following advice from his solicitors he's had to remove the offending references. He's done it, not because he thought what he posted was wrong, in fact he was willing to stand by his words, but he does have a business to run, and he's self-censored his blog for the greater good of the company.
There is a freedom of speech issue here. He should be able to tell people not to use the services of this particular company and also get in some insults, without being threatened with legal action. It may not be big or clever, but what's the point in having a blog if you can't vent your spleen occasionally?