Tor editor Anna Genoese has come up with perhaps the most insightful biz-related blog post of the year, and if you're a writer, published or non, it's required reading. Why? Because she gets into the nitty-gritty of how publishers conduct profit and loss, the number-crunching that determines what sort of advance will be paid out and how a book is expected to sell.

In part one, Genoese runs the numbers for a mass market original that didn't perform up to expectations. So much so that it actually ended up losing the publisher over $20,000. But as Genoese points out, "this is totally normal. This is an average book! Okay, it's a slightly cynical look at the average mass original, but you won't find too many editors who don't have a couple of these on their list."

Part two will look at "a book that goes from hardcover into mass market, with a positive/neutral P&L." No doubt the math will prove just as illuminating, if not more.