In playing with IPv6 at home, the the biggest problem has been firewalling. Vista and windows 7 assume you are either on a public IP (aka in a coffee shop) or some kind of NAT'd or external fire walled environment (aka on a slightly more trusted IP).
At home, my little LAN is fully trusted. I like to keep all my gear open, full sharing, no passwords. Anything more is a hassle.
The problem is, with IPv6 you open your LAN to the outside world. That is okay *if* you have a firewall on your router. My router (d-link DIR-825) doesnt support firewalls for IPv6. neither does OpenWRT, which can run on that box too.
Until they make low-cost consumer routers that support comprehensive IPv6 firewalling, I can't really justify running IPv6 at home.