Ok, I'll be odd man out and come to the defense of spitting. For
enjoyment, I obviously prefer to drink wine, following the evolution in
the bottle. But......

1) I have limited funds to spend on wine. I often take the opportunity
to go to large store tastings, or trade events (I know enough ITB folks
to get in to most). These are usually daytime, and I don't want to get
snockered. Besides, if I swallow I really would lose some analytical
ability after a while (some of these tastings feature 200 wines, and I
might try to taste 50-60 I'm interested in. Occasionally you see
someone who doesn't spit there, it's a sad sight. I regard these
occasions as research for my financial good, not as pleasure.

2) Similarly, I occasionally participate in rather large verticals or
horizontals. I think we had 29 2000 Bordeauxes at one, and I'm planning
a Gruaud vertical where we have at least 19 vintages. In those
situations, I drink more than at a trade tasting (adn have a grand old
time), but I still don't want to drink THAT much. So I'll spit the ones
I like least, so I can fully enjoy others.

I tend to put disclaimers on my notes from trade or store tastings,
since I would never claim that 1 oz pours are the best way to fully
explore a wine. But, for my purposes, a small pour and a subsequent
spit is still a better guide to MY tastes than any critic. And even
without swallowing one gets a pretty good idea of tannin and acidity
levels, fruit profiles, oak levels, etc.