Hi MPO,
The competitor has a lot of points pointing to his root domain, but for whatever reason they do not point to the subdomain that you are comparing.
For example, if I point a link to example.com (no www), then the root domain metrics for the url www.example.com would be strong, but for the specific subdomain www.example.com they would be weaker.
(boy, this is so confusing when you try to explain it on paper. Here's a post from Rand on subdomains - http://www.seomoz.org/blog/understanding-root-domains-subdomains-vs-subfolders-microsites
Does it matter? Probably not much. It depends where exactly those links are pointing, and what's ranking in the search results. Keep doing what you're doing - getting good links from good sources, and you'll come out on top either way.

