I'm finally getting around to editing my fanfic for actual publishing. Any warnings for Kindle Direct Publishing?
Aside from, you know, "It's Amazon and they'll fuck you out of every penny they can on principle," I can't really speak to it -- I've never used Kindle Direct. My only real experience with pub/sales through Amazon is the fact that when I allowed them to sell my books via Lulu, they artificially inflated my prices because they take such a massive cut of your profits. I have a little more discussion of how that works at this post (look for the paragraph just after "wait, what?").
Now, that said, Amazon is a much, much larger platform for your work than Lulu and unless you are marketing from a platform where you already have a readership (like my blog) then Amazon will probably get more eyeballs on your work. Especially if you are marketing primarily to people who aren't familiar with you, they'd much rather buy from somewhere known, like Kindle, than from a random website they've never encountered like Lulu.
You might peruse @thebibliosphere for more useful information than I can give -- Joy has a lot more experience with Amazon's various fuckeries and has spoken to them pretty extensively. I don't know what the tag is offhand but Joy's tumblr is fun reading anyway, so if you browse around you will also get entertained :D
Readers, if you have info to share, please feel free! Remember to comment or reblog, as I don't repost asks sent in response to other asks.