Annoyingly, Google's help for Keywords isn't all that helpful:
The significance of each keyword reflects how often it's found on your site's pages. [...] If expected keywords are missing from this page, this could be for a couple of reasons:
- The Keywords list will sometimes exclude words that Google has determined to be boilerplate text or common words. The actual excluded words vary from site to site.
So it's clearly not picking up on your words (Log, Copyright, Privacy) as boilerplate/common - do they appear in a similar place in the mark-up on every page, or are they scattered around a bit?
It's possible that once HTML5 has more traction, the semantic elements of <header>, <nav>, <section>, <article> and <footer> would come into play, and therefore content within <section> elements would automatically be considered more significant than the content in <header> or <footer>.