As most rabid Linux zealots know, Linux ports are available on several architectures - x86, Sparc, PowerPC, and Alpha, among others. Unless otherwise stated, this document refers to the x86 version of Linux, although as code stabilizes and 2.2.0 evolves, I'm sure that IPv6 code will be ported everywhere.
As of this writing, the latest experimental Linux kernel is 2.1.27, but I'm sure that's changed by the time you read this. IPv6 support is now supported in the kernel as a compile-time option. The goal is to bring a stabilized IPv6 to 2.2.0, when it arrives.
There are several useful mailing lists that you may want to subscribe to:
This list is for people involved in, or just plain interested in, the work being down to bring IPv6 to Linux. This is the place where the developers hang out.
Subscription Requests to: majordomo@nuclecu.unam.mx.
Archives:
A general mailing list about Linux networking - subscribe via linux-net@vger.rutgers.edu.
Similar to Linux-net, except (you guessed it!) about issues related to the Linux kernel. Subscriptions to linux-kernel@vger.rutgers.edu.