I'm the guest on the StackOverflow podcast with Joel Spolsky and Jeff Atwood. w00t!
We talk about everything from early internet history, to IPv6, to how to scale a really really really large web site. Here's the episode page and link to the audio. (Tons of links on the episode page).
Check out their website for sysadmins Q&As at http://serverfault.com
Thanks to Joel and Jeff for having me on the show! I listen every week!
Funny that you should be mentioning IPv6 and the list of dumb things to check. At my company we've been steadily deploying IPv6 over the last few years, and one of the big gotchas is when a host has IPv6 configured in DNS but the IPv6 networking is broken for some reason (sometimes it just doesn't get the attention that IPv4 does!). Many IP stacks nowadays will try the IPv6 address first, and this creates very noticeable pause before it switches over to IPv4.
There are other gotchas that happen in the interaction between IPv4 and IPv6. For instance, updating a firewall rule for one but forgetting the other, leaving a gaping hole wide open or denying access for an important service.
I suspect problems like these may become more common as IPv6 gains traction, and it seems to me to be a perfect thing to add to your list.