Definitely great domain because of possibilities and the better percentage of finding a nice end-user anywhere.Other general domains, for example, are harder to locate end-users. But DN, domain name, will be a lot easier to find am end-user, due to many domaining forums and activity. So automatically it gains a lot of potential value, and is above reg-fee, (not that it would be under.)
The DN part is clearly used for domain names, domaining, and on and on. However, it isn't limited to what others have said (registrars, portfolios.) It can also be used for hosting websites. Hence the storage. Also, similar to DigiPawn, you can store domains for people. Possibly have a service that monitors and tracks all domains for people, (those who have hundreds or thousands.) Lots of possibilities with this one, and i don't need to repeat what others have said.
Statistically speaking, its low in value. Estibot, smartpagerank, and dnscoop all display poorly. No links, 25 days old, no PR, not anything. That hurts the stats value, which IMO is crucial. However, with this type of domain, it's clearly more the speculative factor, and not stats.
Value: Undeveloped is mid $xx. The domain market is dipping a little bit with lower priced domains, (which is another discussion in general,) probably due to the souring economy. Part-time domainers may want to spend less on cheaper domains. Because this doesn't fall under $x,xxx ^ category, it may be hurting.
Developed however, can be worth a ton more because of the possibilities. Can't set a price on this one for developed because I don't know what way you can choose, blog registrar, host. Anywhere from $xxx to even $xx,xxx (if you go with hosting/registrar and a lot.) More or less $xxx
:imho: Keep it, develop something big, then sell.