Who's your favorite author? What makes them your favorite?
I have a few...
The obvious (well, obvious to me at least) JK Rowling. She captivated an entire generation (and more) with her characters, plots and settings. She ignited reluctant readers into action, kept many regular readers up into the wee hours of the morning and built an empire with an orphaned boy wizard.
Next up I would have to list Garth Nix. His Abhorsen series is well written with good characters and a well thought out alternate world.