jeans is my casual choice at home, or on Fridays at work. slacks for work, with a crisp, collared shirt. Ties are very rare now. The only time I wore a tie in 2010, was to our company Christmas party last Friday (ironically, the opposite of casual Friday) because I was wearing a suit.
Women seem to roam the range from dressed up to casual at work. I rarely see nylons at all, and my wife was worried that she would be inappropriately dressed at the Christmas party because she was bare-legged. This was not the case as almost every girl there had bare legs, or very fancy stockings on.
Casual wear isn't always jeans for women. I have to say that the recent trend towards Lululemon leggings is nothing but good:
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