Short form, she sold a book and the person she sold it to started making things from that design; and she had someone steal both her book design on ebay as well as her code and listing, and even inpersonate her.
My response, not so much about her post as about people in general:
Yeah, there's all sorts of levels there... I've seen people post tutorials and then get furious when someone else posts about their finished project from using that tutorial (why post a tutorial if you don't want anyone to follow it?)... and if Keith Smith threw a fit every time someone made a book using the instructions he's published, he'd have no time to do anything else (why publish an instruction manual if you don't want someone to use it? -- not attributing that attitude to him!)... Or if my coworker who studied bookbinding at North Bennet Street started teaching fine binding (in which there's not so much variation as in "book sculpture"), and they went after her for copying their ideas... but, on the other hand, impersonating the person whose work you're copying and selling is something else entirely! There was an issue on etsy a while back where someone was using someone else's images and descriptions to "sell" nonexistent items (read more about it here: http://patchworkpottery.blogspot.com/2009/02/scam-on-etsy.html )... But there's also coincidences, like one I was amused by (when I made this one http://dangandblast.blogspot.com/2008/08/city-streets.html using a simple binding structure and a commonly-available paper, and subsequently saw this one on another site http://dangandblast.blogspot.com/2008/09/not-book-i-made.html with the same common binding structure and a different section of the same paper). When people use the same basic concepts and shop from the same suppliers, you'll end up with some overlap... there's quite a few people who've, without a pattern and without knowing about each other, made 2x2 ribbed scarves with identical yarn before. Then there's people who post free patterns (my two favorite being Oh, Fransson's Margaret Bag and Rae's Buttercup Bag (which has what I think is a good solution at that post)), and expect people to use them (that's why they're posting them!), but ask people not to sell their finished products (and justifiably get angry when that happens). Neither bag is massively-enough different from other things out there, though, that they'd have a leg to stand on if someone made a *similar* product for sale... like how Vera Bradley fabric purses were all the rage, but when other people said, "hmm, cloth purse out of busy fabric, I could do that," it wasn't stealing her idea in any sort of bad way, although it was certainly derivative work (and usually priced accordingly).
I've gotten rambly... guess what I'm trying to say is, I think in your specific case about the ebay seller you're right (and in other cases it's also pretty blatant, especially when someone says "feel free to use this but don't sell it"), but there's other people out there who share their ideas, or even teach people (who've paid for the class) exactly how to make something, and then pitch a tantrum when someone else says, "hey, good idea, I'd like to try that!", even when the someone-else is just posting it on their blog and isn't selling it or anything... there's levels to all these things...
(My sister and I are going to make a million dollars off of this new apron concept that she's come up with and I've made, as she has vision and I have craft-ability, but that's why I'm not telling the world all the details of it or describing how it's made until I finish working on the design and we actually get some legal cover for it!)