While I have limited experience in PGP infrastructure, I have spent a great deal of time with X.500 & X509 infrastructure (sympathy appreciated).
i watched that and see the parallel.
The key service folk (PGP and anyone IETF-izing the X509 world, and the IPSEC folk for that matter) would be doing a Huge Service to Humanity if they simply *defined* the manner in which key servers will find each other using the DNS.
i am not convinced. the email address space you describe maps well to the dns as it too is hierarchic (in fact is the identical hierarchy:-). the pgp key space is not obviously hierarchic, but rather a non-directed and cyclic graph. so using the dns, e.g. srv rrs, to find a keyserver is not a mapping so obvious that i can see it. unless you are suggesting that looking for the public key for randy@psg.com should follow the dns hierarchy for psg.com. this forces all keys ids to be domain name based, which is not a restriction in pgp. it also does not work in obvious ways for reverse lookup, though i can envision a hack similar to in-addr.arpa (yuck). randy