All things being equal, there is only marginal benefit from a .edu link over links from other top level domains (TLD’s). Assuming you have two different pages with the same domain level and page level inbound and outbound link profile, one with a .edu TLD and one with a .com TLD, the .edu is slightly more valuable if you believe the search engines are using a form of the TrustRank algorithm due to .edu sites being selected as ‘good’ seed sites. I personally believe that they are using TrustRank or something similar, so I believe it to be true.
However ….
Since the situation outlined above with two identical sites having the same inbound and outbound link profiles is unlikely, you should forget about TLD’s when looking for links and use traditional link analysis methods to determine quality. The inherent value in a .edu link is it’s more likely to have a higher number of trusted, authority .edu backlinks than other TLDs, but just like there are many worthless .com links, there are also many .edu links that either link out to bad neighborhoods and promote spam, are off-topic, and/or do not present worthwhile linking opportunities for other reasons. When investigating link acquisitions, domain age, .edu backlinks, anchor text, and the community your potential link partner belongs to are far more important than whether or not it lies on a .edu.