Forrester Research recently wrote about the increased use of sponsored conversations (such as blogging)--and the post immediately provoked comments throughout the blogosphere and Twitterdom. If you read nothing else in Forrester's post, scroll down to the end and look at the excellent summary matrix of what constitutes a sponsored conversation, what constitutes advertising, and what constitutes PR.
Are sponsored conversations (in which bloggers are paid for writing or receive products or other considerations) ethical? Forrester says yes if (1) sponsorship is disclosed and (2) the blogger is free to say whatever he/she wants in his/her own words. Forrester's Jeremiah Owyang maintains a list of sponsored conversations in multiple media.
Other bloggers have added their thoughts to the discussion. Here's a Network World post against sponsored blogging; Conversation Agent rounded up a number of comments here; and here's a call, from the Intl Blogging & New Media Assn, for a summit on the issue.
IMHO, sponsored conversations are dicey. Transparency is paramount to credibility. That's why advertorials have to be clearly marked as such, letting readers know that they should be aware that a sponsor is involved--even if the sponsor hasn't seen or contributed to the content.
Same with blogging and tweeting. I follow some corporate blogs and Twitterers, always mindful of who they work for. If McDonald's or Starbucks or Dell sponsored my blog, it might influence what I say even if I'm not aware of that subtle influence. And it might influence what you think of what I say. Not worth it, is what I say.
Let me add that sponsored blogging/tweeting is distinctly different from posting on a blog that is sponsored by a corporation or brand.
To bloggers and tweeters who have no commercial sponsors, I say: Your independence and your unique views of the world are what I value. Let the conversations continue.