Let's turn that question on its head: should you link to discoverthenetwork.com, or should you link to the version with www? Wait, there are even more choices ahead. You can also link to either version in the .net and .org TLDs. And, it gets even better, because you can link to all six at discoverthenetworks. And, all of those return a 200 instead of 301s pointing to a main domain.

Let's look at a few PR values:
www.dtn.com: PR5
dtn.com: PR3
www.dtn.net: PR0
www.dtns.org: PR0

So, why am I telling you this? Because I've already sent them two emails telling them to fix and the many other problems at their site, and they've failed to do so. Which is a bit frustrating for me, since I've linked to them from many posts here and elsewhere, but they don't seem to be able to do their part to try to make their service as effective as it could be.

I mean, this blogger is hardly an SEO expert, and this site has its own problems, some of which I'm still fixing or have given up on. But, DTN is a newer site, and they (I would imagine) have enough of a budget to actually do something.

So, if you have some pull with them, please suggest they finally fix their site. Some of these changes - like redirecting all 11 alternate URLs to one URL - would take about 15 minutes of work if that.