There seems to be much confusion about the debian trademarks. I'm confused too, so I'm trying to collect my notes into a web page here to summarise the current position and correct some of the worst myths like "Debian (through SPI) lacks, however, a Policy regarding the use of trademark" (quote from a conference session description).
The latest version of this page should be at http://people.debian.org/~mjr/legal/trademarks.html This is not a summary of how to apply the DFSG to trademarks that affect debian packages.Disclaimer: I am a debian developer and a member of the spi-trademark committee who has reported on it to SPI board and the debian project, but this page is just my view and not approved by either organisation. I believe that the debian branding should be available to all contributors and harmable by none, with a non-discriminatory licence, but I know that's not where we are today.
Copyright and trademark laws do different things. To understand more about the differences, try a crash course from iusmentis or a similar site. The usual objection is not to the dealing in the logo (covered by copyright), but in trading on the logo (covered by trade marks law).
Just to be clear, the two debian logos are currently under the restrictive copyright licences described on http://www.debian.org/logos/ (set by votes in 1999) and not currently suitable for inclusion in the debian operating system, but the project is currently in the process of changing this. I expect an announcement from SPI soon.
The font used for the "debian" is Poppl Laudation Condensed according to Alfie and Craig Small
debian is a registered trademark owned by SPI in the United States, and managed by the debian project, as explained on their site. A similar trademark is registered by debian JP and SPI in Japan and maybe owned by SPI in France and Norway.
It's not absolutely necessary to register to have a trademark, as explained on Groklaw but it makes some things clearer, in exchange for some expense.
The main general licensing of the trademark continues to be the 1998 Announcement About the Debian Trademark (confirmed in October 2003). Additionally, I believe specific licences have been granted to The Debian-UK Society and various Debian Labs (even though they are businesses which use "debian" in their name), while some others have been asked to stop.
Unresolved problems include the Spanish registration which SPI is acting against still.
There is an spi-trademark committee but it has less than 6 active members, so it mostly just reacts to enquiries and reports that are sent directly to it. If you can help, sign up and introduce yourself to the list.
Matthew Garrett was reported in August 2004 as working on a trademark license, but little resulted from that effort, as far as I can see in the spi-trademark archives. Benj. Mako Hill drafted a Free Trademark License but it has not been adopted yet. Branden Robinson "is delegated the authority to direct the SPI board in regards to copyright and trademark licensing" at present and some of his work is recorded on wiki.d.o.
Personally, I'm not surprised that there was not much progress on our trademark during 2006-2007, with a Debian Project Leader who writes utter rubbish like "The DFSG [...] doesn't cover patents or trademarks" but maybe we can get moving again now, and make debian more fun by fixing this mess at long last, instead of it being thrown up over our shoes each time we complain about someone else using trademarks to obstruct free software.
If there is robust legal opinion that one cannot permit copying while restricting trademark use, please post it before we make a mistake. In several years, I've not seen anything substantial. Moreover, I thought Sun's Java mascot was heading in a similar direction.
There was an enlightening discussion on debian-legal about the differences in April 2004.
If you use the debian trademark as permitted, it will help us if you make a donation even though you are not required to do so.
Please send contributions as patches to the html source code or plain text to me (contact details should be mjr at debian.o).