LinuxQuestions.org - General Question about Distro Logos?

First part of the Permitted Usage section@

Quote:

Permitted use

Certain usages of the Trademarks are fine and no specific permission from us is needed.

Community advocacy.
Ubuntu is built by, and largely for, its community. We share access to the Trademarks with the entire community for the purposes of discussion, development and advocacy. We recognise that most of the open source discussion and development areas are for non-commercial purposes and will allow the use of the trademarks in this context, provided:

the Trademark is used in a manner consistent with the Usage Guidelines below
there is no commercial intent behind the use
what you are referring to is in fact Ubuntu. If someone is confused into thinking that what isn't Ubuntu is in fact Ubuntu, you are probably doing something wrong
there is no suggestion (through words or appearance) that your project is approved, sponsored, or affiliated with Ubuntu or its related projects unless it actually has been approved by and is accountable to the Ubuntu Community Council

<snip>

Commentary and parody.
The Ubuntu trademarks are designed to cover use of a mark to imply origin or endorsement by the project. When a user downloads something called Ubuntu, they should know it comes from the Ubuntu project. This helps Ubuntu build a reputation that will not be damaged by confusion around what is, and isn't, Ubuntu. Using the trademarks in your discussion, commentary, criticism or parody, in ways that unequivocally do not imply endorsement, is permissible. Anyone is free to write articles, create websites, blog about, or talk about Ubuntu -- as long as it's clear to everyone -- including people completely unfamiliar with Ubuntu -- that they are simply referring to Ubuntu and in no way speaking for Canonical, or the Ubuntu project.

So really, if it's a personal blog and you don't use the logo for selling and if you are commenting on/reviewing Ubuntu, it looks to be fine. They are more bothered by people remixing (possibly badly) and saying "this is Ubuntu" or any other form of pretending you are part of the team.