A question from the gallery:
Now that Redshirts has become a New York Times bestseller, to what do you attribute its success? Anything that could be replicated by the rest of us?
To answer the second part first: Maybe. To answer the first part second, there are several factors which I think came into play, which I will lay out below.
Honestly, I feel this list is important for all writers to understand. There's a lot of guesswork that goes into a commercially successful novel, and what works for someone like Scalzi won't necessarily work for a different writer (even one in the same genre with a similar publisher and/or fanbase).