The temporal nature of blogs makes it an ill-suited medium for a traditional manifesto. Manifestos seem so absolute - a public, didactic declaration of one's thoughts and views - clearcut and unyielding. Blogs, however, die without constant update. Would anyone read a blog with just one entry, dated decades earlier? What goes viral on the web lack any of the characteristics of a manifesto - (Ass Pennies* vs. Vers une architecture).
Yet because of the ability to constantly update, the blog is more suited to he true purpose of the manifesto: expressing one's thoughts and views. How many of the manifestos and monographs have we read have the authors' work or later publications modified or retracted what they originally declared? How many times are those edits heeded or mentioned? The published manifesto is static, a declaration in time with a tendency to speak for all mankind. The blog is personal, the reader is always aware that someone typed these words out on their laptop or PC, possibly drunk, possibly in their underwear. And if your blog is open to comments, your manifesto can be immediately detracted, criticized or flamed by anyone - ANYONE - and given that they are in the same medium, comments are automatically on the same level as the blog post. Any criticism of published manifestos aren't attached to the actual document.
So in random and personal rambling, I'm just going to throw out there with no evidence or three supporting points, that maybe the blog is a democratizer/humanizer and with access and inundation of everyone's** thoughts, the publication of one person's thoughts are de-deified and more open to contestation (that is a real word. I checked.)
*I do not mean to detract from the value of Ass Pennies at all.
**"everyone" with access to a computer and internet. Which is not really everyone.