I would not lie to you, bois & grrlz.
During the last UT99 server IP change, my IPv6 tunnel with Hurricane Electric , which had been running fine since February, got fucked. One thing led to another and I never got around to fixing it until today. Once I fixed it I realized my IPv6 name resolution was not optimal and I fixed that, too. It was just a minor PowerDNS tweak to tell the recursor what address to do IPv6 name resolution on. Once that was done, I didn't have to depend on the special IPv4+6 SQUID proxy I had set up.
Another by-golly swell thing that happened in February was the mDNS RFC finally got rewritten. This sucker has been languishing for six years.
Why is it back now? If I had to guess I'd say it's because of the rise of the iPad, since from Day One mDNS was always an Apple Thing™.
What does mDNS do for you? Apple fanboys will always tell you that their MAC just works. In fact, if you ask them how it does that, they don't know, and they'll admit they don't know.
All they know, they'll say, is it just works.
And that is the sum total of their knowledge about MACs (ask one someday, s/he will gladly tell you).
Apparently they're not inquisitive enough to find out why. Or maybe they're just stoopit.
mDNS is one of those things that enable that particular feature. When a MAC fanboy walks into an environment that supports mDNS (not very common in the Windows world), all local devices are available. Need to print? Most printers, copiers, and fax combo device built in the last five years will be available because of mDNS. Want to listen to some music? You can hook up to a local user's iTunes and get in the groove.
All sorts of Good Shit will be available to you.
(NOTE: security wonks such as myself don't think this is necessarily a Good Thing)
When you combine mDNS with IPv6, like I did today, the future will be revealed to you.
Soon, your ISP will be giving you a shitzillion IPv6 addresses, more than you will ever need. Every device in your home will have its own IPv6 address and those devices will need to talk to each other and you. mDNS will help enable that communication.
While your devices are chatting, you still have to make sure that some IPv6 enabled samovar in East Fuckistan isn't attacking your Mr. Coffee in Cleveland, so you'll still need a firewall. But—and this is the best part—you'll be able to forget everything you ever didn't want to know about NAT, which has been forced on you because of that one crappy IPv4 address your ISP currently allows you.
The future is coming.