Powdork - 4:04 pm on Nov 19, 2004 (gmt 0)
There is a theory that outbound links help a page rank and I believe it to be true at least for the terms in the anchor text of the outbound link. Others believe that outbound links don't help at all. They often give the example of webmasterworld, which has no outbound links that Google can see.
Do what best serves your users.