It depends on the activity and your individual needs. If you're running, the socks will DEFINITELY make a difference. New Balance and SmartWool make running specific socks that provide temperature regulation, extra arch support and combat odor causing bacteria. I run in either the New Balance Coolmax N260 or the SmartWool PhD Running Light Micro. Both give me extra support in the arch area that helps to reduce fatigue from those extra trying jogs. They also keep my feet cool which is important considering they're taking the impact of the run with direct contact to the surface. And don't be afraid of the 'Wool' in SmartWool. It's exactly how it sounds, SMART! Made with Merino wool and fine combed to take out the 'itch'. SmartWool PhD collection in particular lives up to its intelligent sounding name. Check out the specs below to see why.

For just an every day sock I would go with what is most comfortable. If you don't have foot pain than you don't necessarily need the extra cushioning under foot that New Balance and SmartWool build into alot of their styles, although it could be considered a preventative measure. To show off just how smart they are, SmartWool also addresses the non-cushion and micro-cushion needs with some of their casual styles. And if you're strictly going for the 'cute' factor they have fun patterns as well, like the Margarita, the Saturnsphere for women and the Diamond Jim and Stripedo for men.I obviously wear New Balance and SmartWool running and casual socks for the comfort value. But you have to just go with what's comfortable for you. Believe me! Your feet will let you know when they are unhappy! Good Luck!