DNS issue, solved
Earlier, when I posted resolv.conf, I spotted what might be a problem:
Network Manager was active, even though I'd turned it off long ago.
Using the GUI tool, I turned it off again. This morning's updates
included some kmod-nvidia stuff and later I found that one of my games
(Plants vs Zombies, under Wine) wasn't loading, so I tried logging out
and back in. Alas, X wouldn't start, forcing a reboot. (Only a little
under 4 days of uptime, so no great loss.) Everything came up properly,
I have DNS without playing games and Network Manager didn't activate.
Now, the only question remaining is, what turned it back on in the first
place, and that's not exactly urgent.
Note: the first time I sent this out, I got back a bounce on a
mail-loop. If anybody gets this twice, sorry.