Thanks to DrCoachChris for this tip-off: apparently, the recent Apple MacOS X security update (Security Update 2006-003 1.0) may cause bootp process explosions and thus prevent you from being able to log in to the new Intel iMacs and perhaps the Intel Mac Minis (though his MacBook Pro survived it fine). He's trying to track things down (and was tipped off by someone else's blog post), but I'll share the advice for you: do not apply this update to an Intel-based Macintosh until you do some checking first. My guess is we'll see Security Update 2006-003 1.0v2 or 1.1 within a few days.
(If this turns out to be accurate, he scooped Macintouch. Well done, Chris!)
[Updated 10:35 AM] There are problems all over the place with this update. Chris just told me that MacFixIt is having solid coverage of this emerging catastrophe (things as bad as "hosed FireWire drivers"). We've implemented a team decision not to apply this patch to any Macintosh, PowerPC or Intel, until Apple puts out a revision.
