A couple of years ago, a blog post of mine appeared in the List of References of a paper. Unfortunately, the form in which it was cited was this:
#16 Zivkovic B. Clock tutorial #6: To entrain or not to entrain, that is the question. (2005); Available at: http://circadiana.blogspot.com.
As you can see, it is far from specific. The actual URL of the post is http://circadiana.blogspot.com/2005/02/clock-tutorial-6-to-entrain-or-not-to.html. When I reposted it here I added on the bottom what I thought would be the Proper Reference to this post:
Zivkovic, BD (2005/2006) Clock Tutorial #6: To Entrain Or Not To Entrain, That Is The Question. A Blog Around The Clock, http://scienceblogs.com/clock/2006/08/clock_tutorial_6_to_entrain_or.php
I even contacted the authors about this, but nothing was done to fix it.
As that post was for a long time the only example of a cited blog-post, it was kinda OK (except for me alone). But now that the practice is spreading, some uniformity is neccessary and authors/editors need to be informed about it. Now, The NLM Style Guide for Authors, Editors, and Publishers has added the official rules for citing blog posts (via Medgadget):
Bookmark those and remember to use them!
Update: Now that I took a second look and removed my perceptual blind-spots, prompted by a commenter, I see that they are actully not including correct permalinks in their references. I will contact them and you should, too.