The typical approach would be to bind the key to a command, rather than another key sequence. In your case you want to call org-shiftup with an argument. For example:

(define-key org-mode-map (kbd "<M-S-up>")
   (lambda () (interactive) (org-shiftup 7)))

Alternatively you can bind one key sequence to another as in the example you cited. This works for me:

(define-key org-mode-map (kbd "<M-S-up>") (kbd "C-u 7 <S-up>"))

As @Tyler pointed out, when defining keys for a specific mode you generally want to use a mode hook or eval-after-load so that the key is not defined until the mode's keymap has been defined.

A few general tips:

• Use C-h k to find that S-up is bound to org-shiftup.
• Use C-h f define-key to read the doc for define-key. It looks like you swapped the arguments and may not be familiar with keymaps.
• As noted in the comments, use C-h k to see the appropriate key syntax -- when using up, you need the <>.

The typical approach would be to bind the key to a command, rather than another key sequence. In your case you want to call org-shiftup with an argument. For example:

(define-key org-mode-map (kbd "<M-S-up>")
   (lambda () (interactive) (org-shiftup 7)))

Alternatively you can bind one key sequence to another as in the example you cited. This works for me:

(define-key org-mode-map (kbd "<M-S-up>") (kbd "C-u 7 <S-up>"))

As @Tyler pointed out, when defining keys for a specific mode you generally want to use a mode hook or eval-after-load so that the key is not defined until the mode's keymap has been defined.

A few general tips:

• Use C-h k to find that S-up is bound to org-shiftup.
• Use C-h f define-key to read the doc for define-key. It looks like you swapped the arguments and may not be familiar with keymaps.
• As noted in the comments, use C-h k to see the appropriate key syntax -- when using up, you need the <>.
• To really understand key maps and key bindings, refer to the Elisp manual. There is also a great overview on Mastering Emacs.