[Orgmode] Diffing org files with orgmode results

[lanas]

Folks,

  This may be far-fetched.  Let's say that there's an org file whose
purpose is to maintain a list of tasks.  The file is viewable by
everyone in its html incarnation.  It could be useful to produce a
html difference between updates of that file that would look like and
org file.

  For instance, the file would have entries like:

  - [-] Add support for Australian customers [2/4]
    - [X] Menu entry for country code
    - [X] Change behaviour of device
    - [ ] Test
    - [ ] Update user manual

  And would be updated like:

  - [-] Add support for Australian customers [3/5]
    - [X] Menu entry for country code
    - [X] Menu entry for extra delay
    - [X] Change behaviour of device
    - [X] Test
    - [ ] Update user manual

  The diffrence would look like:

  - [-] Add support for Australian customers [3/5]
    - [X] Menu entry for extra delay
    - [X] Test

  The difference would be a separate html file with a 'NEW' link
pointing to it for convenience.

  Is there a utility that would produce a org-formatted difference
along these lines ?  Diff could obviously make it, but then the actual
diff output would have to be processed to produce a org file that could
be converted to html.

Cheers,

Al