We support DNSCrypt which will encrypt your DNS traffic between you and us. That's the last mile, at least. We support DNSCurve for the other hops, but almost nobody else does.
That's probably enough for most uses, as the unencrypted queries entering the cache are mixed with millions of other people's.
Myself, I'm still wary of providing data to any third party. Maybe it isn't the case any more, but at least recently, OpenDNS stored identifiable logs forever and potentially resold that data.
DNSCrypt meets this need and is based on the same crypto from DJB. If you're running a full-blown resolver, I'm not sure if DNSCurve works if you forward to us... I'd have to find out.
Myself, I'm still wary of providing data to any third party. Maybe it isn't the case any more, but at least recently, OpenDNS stored identifiable logs forever and potentially resold that data.