This is the current link tag in the header at 8th light's blog:
<link rel="alternate" type="application/atom+xml" title="Subscribe to the 8th Light blog" href="/atom.xml"/>
Because /atom.xml doesn't exist, that should be:
<link rel="alternate" type="application/atom+xml" title="Subscribe to the 8th Light blog" href="/feed/atom.xml"/>
As a result, tools like Google Reader and Safari aren't able to discover the feed. (Or rather, they think they are, but see that it has no articles)