[Late to the party.]
I really hate these and just posted it in the Moderators forum.
Unless someone is asking for clarification or enhancing the content in some way (i.e., different perspective or a unique country-specific requirement), I think this is spam-y. If there is a meaningful reply, it ends up getting buried under multiple worthless "great blog" and "thanks" replies.
Not sure how to handle this other than to delete every reply that I see in the blogs in the area that I moderate. Would love to get some direction from the SCN folks.