I’ve had very few positive experiences with Comcast, but I have to hand it to them — they did a great job on their IPv6 deployment. My modem died today due to a power surge so I figured now would be a good time to get an IPv6 capable modem so I could have native IPv6 support instead of using a tunnel.
IPv6 support worked on the router as soon as I powered it on. In order to get IPv6 working on all of the devices connected to my Airport Extreme, I simply had to check the “Enable IPv6 Connection Sharing” option:
Restart router and done. No fuss. If anything, Comcast made IPv6 easier than Apple did. Which is something else I noticed — Chrome seems to prefer IPv6 over IPv4 and Safari is the opposite.