You should be more concerned with whether or not you’re linking to a good quality site that your users will find useful. Recommending good sites makes you a resource. People bookmark resources and return to them. You should link to great websites and pages regardless of whether or not they give you a link back. If every link out from your website is a reciprocal link, what kind of message does that send to the search engine?
Agreed. That’s my way of thinking. The zero pagerank page though should be a good resource site though.