It seems (I just checked with the link you provided) that it's a wrong use of the trademark indica.
if you use:
[logo] Joomla!
then you use the Registered Trademark then you MUST use the ®
Thanks

All the stuff in Chiara's folder when the revised brand manual was published uses the ® so I'd go with that (that's where I've gone to get graphics as I've needed them).

and more than "because" of Chiara, because the US Patent & Trademark Office is saying to do so:
see Serial N°77224536 and N°77226768 ont the http://www.uspto.gov/
and even: https://docs.joomla.org/Joomla:Brand_Identity_Elements/Official_Logo
(still underconstruction but OK) ;)

Note: we do not need to use it at the top logo when the footer specifies that Joomla! is registered the way it is for example on the the JDoc site.

I'll update it - we seem to have a serious problem when the official files being served up from joomla.org don't even have the right marks lol

This should be closed?

would say yes as legally speaking and regarding the obligations related to TMs, everything is ok at this point.

The joomla_logo_black.jpg file is gone so we're serving a dead image on our Markdown page right now. Is https://www.joomla.org/images/logos/Horizontal/PNG/Joomla%20Logo%20Horz%20Color%20FLAT.png right or not?

The one above is registered then can't be used without the R indica.
Please see: https://docs.joomla.org/Joomla:Brand_Identity_Elements/Official_Logo
and/or
https://drive.google.com/a/community.joomla.org/folderview?id=0B-WMsfRg_wivSV83SzZzZ2tRM2M&usp=sharing&urp=https%3A%2F%2Fdrive.google.com%2Ffolderview%3Fid%3D0B-WMsfRg_w#grid

If you need the Logo (black) only, then the ™ is needed as it is not registered on its own.