I have all of these thoughts, ideas that I want to just get out there. I have a notebook (which I'm not smart enough to bring with me everywhere), and about 50 ideas a day. Most of these aren't terribly workable or they are sloppy, uncreated, boring. Etsy is a place where the unusual finds its niche.
Some of my friends are on Etsy. The ones with the most success are the ones who either make classic, elegant pieces (mostly jewelry) or the ones who make funkiest stuff. There is room for both of those. I'm not sure how much more room there is for people who make normal items. I was browsing today and I saw at least one top that I am almost positive I saw in Knitting Nature and another that looked like a fairly standard tank top (not the Simple Tank, but close).
Now it's understandable that there is a fair amount of derivation. You are looking at blogs or Ravelry or pattern sites or browsing books and an idea sticks in the back of your head. You create something and it looks close to the original. How much of that is OK. How far does a work have to be from the original?
Of course, I haven't made anything yet to put on Etsy, because I am so completely lame. I just keep telling myself next weekend or tomorrow and collecting ideas.