Rich-
Actually, there has...
Perform a few traceroutes from various route-servers to
UDNS1.ULTRADNS.NET.
They are announcing the same netblock from various locales, so basically
it will take you to the closest server. To actually traceroute to a few of
their specific boxen in various locales, change your destination to
ns1.east.ultradns.net, ns1.west.ultradns.net, ns1.jp.ultradns.net, etc.
This was laid out in detail somewhere on their site during the very
generous free trial of their service while in Beta.
-troy