Well, the crashes continue. I've started a new Skyrim character and while it works fine 99% of the time, there's still the occasional jarring crash. I've experimented with hardware, bought a new PSU, tried to work with Bethesda, all to no avail.
While I continued researching, trying to find commonalities between the reported crashes, I ran across something called "TDR" (Timeout Detection and Recovery) used in Microsoft Vista and beyond.
Right now, I'm going to experiment with disabling this feature. The theory is that if the video card is busy, it cannot respond to the OS in the time and the OS will then send a restart command to the video card. Right in the middle of Skyrim, this cannot be good.
To disable TDR in Windows Vista and Windows 7, either change or add the registry settings described in the link above. For me, I set "TdrLevel" to "0" to disable it altogether. I'd rather get a blue screen than what I'm getting now.