Are all impressions good impressions?

According to MediaPost, "HEAD BUTTS MAY LOOK VIOLENT, but it’s a great way to advertise."  Excuse me?  If this is true, then why would MySpace be trying to clean up its content for advertisers?

True or not – it goes to show that you can place your bets as strategically as possible, but then what happens with your brand is out of your control.

Everyone affiliated with your company is a marketer, whether they are on the payroll or whether they’ve paid you!

Some more examples:  Seth Godin blogged recently about receptionists.  Luggage tags displaying your business card and corporate logo.  Bank robbers wearing your apparel.  Customers reviewing your products.

Are all impressions good impressions?  Was Oscar Wilde correct in saying that "There is only one thing in life worse than being talked about, and that is not being talked about"…?