I do, and it depends what your goals are and how much time you want to spend on it. It can be a pain measuring, describing, researching prices, and researching which brands sell well, but if you make enough $, it becomes much less of a pain!
Even though I only sell used items, I do well, because my stock costs almost nothing. It's almost all profit for me to buy an item for a buck and sell it for 10.
I also do well reselling better items I've gotten tired of... boots, jackets, etc. This is worth it to me, too, because I don't feel as bad buying quality items when I know they will hold their value and can be sold later if need be.
I've taught some friends how to sell, and some of them decided it was *not* worth it to them. Reasons ranged from the fact that they found the site hard to navigate, they didn't like answering questions from buyers, it was too hard to measure all the clothing...