skeleton for a basic blog exporter.

*scratch*.el

; use org-make-options-regexp to catch BLOG_DIR in #+BLOG_DIR that can
; be overload in a property :BLOG_DIR:.  Same mechanism for
; BLOG_AUTHOR, BLOG_MAIL, BLOG_CATEGORY, BLOG_TAG.  For this tag,
; BLOG_TAG, we can have multiple values.

(defun ch:org-export-blog ()
  (let* ((tree (org-copy-subtree))
         (buf (generate-new-buffer "*testing export*"))
         (blog_dir "/tmp")
         (blog_author "")
         (blog_mail "")
         (blog_category "")
         (blog_tag "")
         (text (buffer-substring-no-properties (region-beginning) (region-end)))
         (opt-plist (org-combine-plists
                     (org-default-export-plist)
                     (org-infile-export-plist))))
    (set-buffer buf)
    (org-mode)
    (org-paste-subtree 1)
    (goto-char (point-min))
    (org-mark-subtree)
    (org-activate-mark)
    (let ((rb (region-beginning))
          (re (region-end))
          (fname (concat (file-name-as-directory blog_dir)
                         (downcase
                          (concat
                           (replace-regexp-in-string "[ \t]" "_"
                                                     (save-excursion
                                                       (goto-char (point-min))
                                                       (org-get-heading t t)))
                           ".org")))))
      (message fname)
      (write-region rb re fname nil nil nil nil)
      (deactivate-mark)
      (goto-char (point-min))
      (kill-buffer buf)
      (find-file-other-window fname))))