IPv6 is here

IPv6 is not here; that's the problem. This is a momentous announcement, though.

The final paragraph is somewhat ominous:

"APNIC reiterates that IPv6 is the only means available for the sustained ongoing growth of the Internet, and urges all Members of the Internet industry to move quickly towards its deployment."

In other words, as wmf has already said, IPv6 isn't here. But it needs to be, and soon, otherwise the game is very rapidly going to be up.

IPv6 is in no sense here. The fiat allocators can exhaust their address space completely and the Internet will continue to function indefinitely; it will simply become more expensive (first marginally, and then significantly) to hold a static address.

There are deep problems with universal deployment of IPv6 far beyond simply getting people to throw a switch; the number of popular software packages that will malfunction when addresses cease being representable in scalar integers is large.

The internet can only continue to function "indefinitely" as you so put it unless there are no further end points created or demand comes to a grinding halt by users, servers, anything with a public facing IP address. However, that's not the case and many new devices are requiring public facing addresses, and RIR's typically do not give out new blocks until ~3/4 or more (ARIN requires 80%) of the last block they were given is fully utilised. Now for ISP's issuing dynamic assignment to customers that may only happen during peak periods - but if they don't have addresses to give, they along with everyone else that requires public facing IP addresses have two options: more NAT, or IPv6. Quite frankly the idea of being inside an ISP size NAT like many mobile broadband users are on my home DSL connection is quite an unappealing idea.

There are many problems of deploying v6, nobody is saying it'll be a walk in the park, but end devices (like my €100 Nokia dumb phone and my desktop) support it + can also support transitional methods like 6to4, Teredo etc. Tier 1 providers like NTT have been offering it for years - the problem is now the bit in between the end user and tier 1. I think DSL providers with ancient, non-software upgradable DSLAMs (I'm looking at you Ericsson), and the hundreds of millions of home routers out there doing nothing but IPv4 NAT are the bigger challenge than a few bits of code parsing a longer address.

The internet will not function indefinitely. You're forgetting that some of those software packages that are expecting IPv4 addresses also may not function behind a NAT box/router very well or at all.