gistfile1.el

(defun devlib/buffer-major-mode (buf-or-str)
  "Gets buffer's major mode"
  (save-excursion (set-buffer buf-or-str) major-mode))

(defun open-main-orgfile ()
  (find-file "~/.orgfiles/gtd.org"))

(defun is-org-buffer (buf)
  (let ((mmode (devlib/buffer-major-mode buf)))
    (or (eq mmode 'org-mode)
        (eq mmode 'org-agenda-mode))))

(defun make-org-frame ()  
  "Create a dedicated frame for org-mode"
  (interactive)
  (make-frame (quote ((name . "ORG")
                      (title . "ORG")
                      (unsplittable . nil)
                      (buffer-predicate . is-org-buffer))))
  (select-frame-by-name "ORG")
  (open-main-orgfile))