DNS and OpenDNS have nothing to do with a user. The DNS is an intermediate step between translating a hyperlink into an actual internet address. By installing OpenDNS you overrule a domain's default DNS and use OpenDNS to translate the hyperlink instead.
Anyways like Sida said it's fixed...
actually, DNS can be sort of user related (it's not a global intermediate step, as in, it's all about your ISP) if your ISP hasn't updated the DNS details then there's no way you will be able to see it - the odd thing is that most ISPs refresh their DNS tables every 24 hours, so i don't understand why these people are having issues with it.
I've been told that there are some issues in Vista, that you need to manually clear your DNS cache occasionally so maybe they are vista users - but personally, i was converted to openDNS ages ago, and i love it, it's a lot more reliable than anywhere i know - and if you've updated your nameservers, you can go to the openDNS website and request that they refresh the settings for a specific URL