"There's no financial incentive for ISPs or any companies to invest in IPv6"

Hogwash.

Carriers are running out of public IPv4 addresses. When they do, they'll have to deploy multi-layer NATs (so called Carrier-Grade NAT (CGN) or Large-Scale NAT (LSN)). This presents a problems for the ISP: Cost. Right now, the ISP don't pay for NAT. Their customers do. With CGN/LSN, the ISP now has to run NAT. That's a financial incentive to deploy IPv6 (with IPv6, there is no need for the ISP to run NAT).

*Sigh* Shouldn't you be embarrassed to be so willfully ignorant of reality?

The whole "no, we're not really running out of IPv4" argument has been thoroughly debunked. The IANA free pool is down to 28 /8s. The IANA allocates, on average, 10 /8s per year. So in roughly three years, the IANA free pool will be depleted. The RIR pools will be depleted roughly 12-18 months after that.

The RIRs do replenish their pool by voluntarily returns of unused address blocks and by revoking address space (usually for failure of payment of membership fees by the address holder). According the ARIN, they have 1.08 /8s of voluntarily returned space, and 85 /16s of revoked space. See this presentation - https://www.arin.net/participate/meetings/reports/ARIN_XXIII/pdf/wednesday/rsd.pdf for more details.

In short, addresses are going out faster than they're coming back.

They will possibly use DHCPv6 Prefix Delegation to configure your home router's DHCPv6 server. DHCPv6-PD is one of the more useful aspects of DHCPv6.

Also, Comcast will deploy IPv6 alongside IPv4, so your IPv4-only devices will continue to work just fine.

Could we please stop it with the baseless assertions that the extra 20 bytes in an IPv6 header will cause so many problems? There is no evidence at all to support this claim. The best example of now IPv6 header size is a non-issue is a paper about adding IPv6 support to OpenMPI. The developers investigated potential performance impacts of running MPI over IPv6 in a cluster. They found a whopping 1.4% drop in throughput and no increase in latency (section 4.1). If IPv6 shows such little hit in a such a sensitive environment, I'm very confident that it will work fine in broadband and cellular access networks.

Further, if you were really so concerned with bandwidth, you'd stop using HTML, since it's a remarkably inefficient encoding system.

IP addresses don't identify people. They tell routers where to forward packets.

Can we please move beyond this 1980s idea that IP addresses identify people?

I'm not sure I follow. "Flat use" of IPv4? The IANA has allocated four /8s this year. That's hardly flat.

No one is getting preferential treatment. There have been a handful of legacy /8s reclaimed. But even if we reclaimed all of them, it would only buy 1.5 - 2 years of extra life for the IANA IPv4 pool. Reclaiming "unused" IPv4 addresses isn't a viable long-term plan.

Why do you need to memorize addresses? Use DNS (either static or link-local multicast). It's a lot easier.

Even if you reclaimed all of the legacy /8s, it wouldn't do you much good. The IANA allocates between 10 - 12 /8s per year. At best, reclaiming the legacy /8s would only get you another 18-24 months in the IANA pool.

Rather than spend efforts trying (in vain) to reclaim legacy space, why not deploy IPv6?

Windows Vista, 7, 2008 and 2008 R2 have IPv6 enabled by default.

Well, sort of. ff02::2 is the link-local all routers muticast group. You can ping6 that address to get the link-local address of your router.

Of course, you can also you router advertisements to have your routing table automatically populated. RAs are nice for home networks.

IPv6 is being deployed. For example, this shows the growth in the IPv6 routing table size during 2008: http://www.potaroo.net/ispcol/2009-03/fig7.jpg

You can also check out http://sixy.ch/ for a list of IPv6-accessible web sites. It's growing weekly.

Google has launched their IPv6 trusted tester program, making many of their services reachable over IPv6.

How is it not as intuitive as IPv4?

Why do you have users using IP addresses? That's what DNS is for.

There is no proper use of NAT.