Spokeo: Why can I not import all my contacts from Linkedin?

Social Networks are everywhere and the truth is that it's so hard to keep up with all my contacts these days. I have discovered that Social Network Aggregators are a great way to centralize the way we follow our contacts.

I realize that there are many aggregators out there such as Friendfeed, Socialstream, SocialThing, etc., but one I particularly like is Spokeo. I use Spokeo as it is a very simple tool to help aggregate the contacts that matter most to me. However, that said, I have been experimenting with trying to import my LinkedIn contacts and noticed that it only imports a fraction of my actual 1st level contacts from Linkedin.

Can anyone advise as to why I am unable to import all my contacts from Linkedin? It's highly likely this is simply a case of "user error" so any insight from someone in this community, or better yet- from Spokeo, would be greatly appreciated.

Thanks!