Conventional SEO wisdom states that you want to get as many inbound links as possible, and avoid outbound linking. The theory is that outbound links "bleed PageRank" which lowers your position in the search engines.
But is the theory accurate?
Not according to Google's Matt Cutts. A few days ago, he posted an article on his blog in which he stated that "in the same way that Google trusts sites less when they link to spammy sites or bad neighborhoods, parts of our system encourage links to good sites."
In other words (as some SEO experts have been teaching for a while), outbound links can be good for your search engine ranking. (Just be sure you're linking to good sites.)
This has strong implications for the "link and content exchange" site I launched recently, the design of which depends heavily on the SEO value of outbound links, so I've posted in more detail on the subject there.