To add to my post above. It's very "casual" in Colorado. You can wear jeans to a nice restaurant, but do dress them up with a suit jacket! The climate seems ideal most of the time, not too much of anything, 'cept maybe too much dryness right now!
People are freindly, because they're happy! The sun shines over 300 days a year. Being a shut in myself, I find that extremely valuable in your everyday outlook.
People seem to truly care for the environment out here. I've been here 35 years from the east coast, never looked back.