As anyone paying attention on Etsy knows, the default search is now relevancy. The big sellers who relied solely on renewing to get exposure are having a somewhat hilarious cow in the forums because they don't want to have to learn about SEO and implement it for their shops. This is really paying off in a big way for little sellers like me who are willing to do the SEO work to be seen. I can hardly believe it - I went from not being able to find myself to being on the first page of all of my targeted searches and even on the first page in one of the very general ones with just one day's work!
Anyway, it's always been hard to get detailed and specific SEO information on Etsy because you aren't generally allowed to talk to anyone technical. The only time I ever got decent technical information was in one man's thread and luckily for all of us he has started a blog that focuses on SEO in general but also has very specific information on Etsy relevancy. He writes in a very accessible style that you don't need to be technical to understand and he even answers questions. Anyway, go read his blog from beginning to end if you're feeling lost or just want to know a bit more. It's called Market My Shop and it's just great.
Please come see my handmade designer plus size sweaters, sweater coats, capes and shrugs at MirabilisFashions.com