There are lots of Smartwool and other kinds of wool fans here at TE. And this is not your grandma's wool--it's soft and not itchy, and some of it's even light enough for warm-weather riding. I have some lightweight smartwool socks that I wear all year round--and I live in Florida.

I'm no expert, but it seems to me that the advantages of good wool apparel over technical synthetics are that it's generally more durable and less likely to retain unwanted odors. Plus, I like that wool is a sustainable natural material.