A few minutes ago I cast my votes from the Nebula Awards preliminary ballot. You could cast up to five votes in any particular category, although some of the categories (such as novellas) didn't have enough preliminary entries, so those stories jumped straight to the final ballot.

My votes, in no particular order:

Novels: Brasyl by Ian McDonald (Pyr, May07) and Making Money by Terry Pratchett (Harper, Sep07);
Novelettes: "If Angels Fight" by Richard Bowes (F&SF, Feb08), "Finisterra" by David Moles (F&SF, Dec07), "The Prophet of Flores" by Ted Kosmatka (Asimov's, Sep07) , and "The Ray Gun: A Love Story" by James Alan Gardner (Asimov's, Feb08);
Short stories: "The Tomb Wife" by Gwyneth Jones (F&SF, Aug07), "Mars: A Traveler's Guide" by Ruth Nestvold (F&SF, Jan08), and "The Dreaming Wind" by Jeffrey Ford (The Coyote Road: Trickster Tales, Ellen Datlow and Terri Windling, Ed., Viking, Jul07).

I should note that the short story category did not include a number of my favorite stories from the eligible period. However, I'm optimistic that the recent rules change for the award will correct problems like this in the future.