On the subject of blogs and emacs the most convenient twitter interface I have found is
http://www.emacswiki.org/cgi-bin/emacs/twit.el
I modified the one function though to default to selected text.
(defun twit-query-for-post (prompt-heading initial-input)
"Query for a Twitter.com post text in the minibuffer."
(read-string (concat prompt-heading " (140 char max): ")
(if initial-input initial-input (if (zerop(length(region-or-word-at-point))) "" (region-or-word-at-point) ))))
