The Federal Trade Commission has published the final version of its guide concerning the use of testimonials and endorsements in advertising.

Last updated in 1980, the guide now includes revisions for advertisers promoting atypical consumer results. As Brian Solis writing for TechCrunch/The Washington Post explains, “advertisers were allowed to get away with promoting unusually positive or outlier experiences in a testimonial as long as they included a disclaimer such as ‘results not typical.’ Long overdue, the revised Guides no longer allow this form of safe harbor.”

Of real concern, however, are new rules for writers using a blog platform to review consumer products.

According to the FTC’s press release, “the post of a blogger who receives cash or in-kind payment to review a product” — let’s say, a free movie screener or a review copy of a book — “is considered an endorsement.” And if you’re writing an endorsement, then you must disclose any “material connections” — that free screener or review copy — to your readers. This, of course, only applies if your review is positive. If you write a scathing screed, it’s pretty clear you’re not being influenced by the those material connections.

The guide includes examples of what constitutes an endorsement when the message is conveyed by bloggers or other “word-of-mouth” marketers. For example, the guide says that a college student “who has earned a reputation as a video game expert” and maintains a blog on gaming software and hardware must disclose to readers when he reviews a gaming system that he received for free (and the manufacturer has an obligation to advise the blogger to make this disclosure in any positive reviews). But the guide says nothing of critics who write for magazines, newspapers, or trade publications and receive free review products all the time.

Solis takes issue with this aspect of the updated guide. “While I agree with the need for disclosure in sponsored posts and tweets, the FTC’s inability to see blogging as a bona fide publishing channel comprised of expert writers and pundits in addition to those consumers willing to exchange content for compensation, is incredibly hazardous.” He continues, writing, “Since the FTC is reviewing incidents on a case-by-case basis, perhaps they will eventually realize the clear division between editorial and advertorial regardless of platform.”

Writing at PCMag.com, Chloe Albanesius thinks that because the FTC seems most concerned with bloggers who make false or misleading claims about a product, “It’s unlikely, therefore, that a positive review for the latest iPhone on a popular gadget blog would result in an FTC investigation.” But she’s sure to include a clause, reminding bloggers that they’re only safe, “provided that the blog reveals that Apple provided them with a free iPhone for testing purposes.”