Since I'm a finalist for the Sidewise Award, I've read up more on the award and its history. Here are some other pertinent facts:
The Sidewise Award is another designated by the calendar year of eligibility rather than the year in which the award is presented. That's why the 2012 winners will be announced at LoneStarCon 3, the 71st Annual World Science Fiction Convention the weekend of August 30, 2013, in San Antonio.
The Short-Form Award is presented for the best work of less than 60,000 words. This includes short stories, novelettes and novellas, and poems. One past winner was a three-issue comic book series.
The Long-Form Award is presented for the best work longer than 60,000 words. This category includes individual novels and longer works.
Nominees were selected by a panel of judges: Stephen Baxter, Evelyn Leeper, Jim Rittenhouse, Stu Shiffman, Kurt Sidaway, and Steven H Silver. This is an international award; Baxter and Sidaway live in the U.K., while the others are American.
Four of the finalists are also from the U.K. - Sales, Hodder, Brennan and Sansom.