Recently, some people started to ask proper IPv6/AAAA record for some of our public mirror infrastructure, like mirror.centos.org, and also msync.centos.org
Reason is that a lot of people are now using IPv6 wherever possible and from a CentOS point of view, we should ensure that everybody can have content over (legacy) ipv4 and ipv6. Funny that I call ipv4 "legacy" as we still have to admit that it's still the default everywhere, even in 2016 with the available pools now exhausted.
While we had already some AAAA records for some of our public nodes (like www.centos.org as an example), I started to "chase" after proper and native ipv6 connectivity for our nodes. That's where I had to take contact with all our valuable sponsors. First thing to say is that we'd like to thank them all for their support for the CentOS Project over the years : it wouldn't have been possible to deliver multiple terrabytes of data per month without their sponsorship !
WRT ipv6 connectivity that's where the results of my quest where really different : while some DCs support ipv6 natively, and even answer you in 5 minutes ...