It's great to have you on board, Gordon.  You must have signed off just
about the time I signed on in 2000.

Let me start by saying that what most people on this list mean when they
use the word "paleo" is simply "those foods which will allow us to
thrive."  Jens brought up a good point that a particular food didn't
necessarily have to be available to us before farming and ranching in
order for it to be good for us today.  Olive oil's the perfect example.

Now some comments on your proposed standard:

"Eat only those foods to which you are genetically adapted"
Agreed One Hundred Percent.

"where genetic adaptation is defined as having occurred before at least
approximately 12 thousand years ago, at the end of the Paleolithic and
before the dawn of agriculture and animal husbandry"

Maybe I'm splitting hairs here, but if it could be shown, and I do NOT
think it can, that genetic change had occurred in the time since an
individual's ancestral abandonment of hunter-gathering which would allow
one to eat the previously inedible, then one should eat the newly-adapted
stuff.  Some argue that dairy falls into this category.  Others alcohol.
Otherwise a good, solid definition.

Another point that needs to be made on the alcohol thing.  I'll give you
for the sake of argument your point that alcohol was generally available
to our ancestors in the form of rotting fruit and that it was actively
sought out.  It's still not paleo because not everything paleo man
consumed was good for him.  Certain South American hunter gatherers, for
instance, are addicted to the plant source of cocaine.  Some folks
probably actively sought out rotting fruit so that they could get wasted.
Doesn't mean that its consumption caused them to thrive.  Mere
availability and regular consumption is not enough.