I'm a little late to the party, but I am finally getting around to reading the stellar Wonderful Wizard of Oz comic adaptation written by Eric Shanower. (And published by Marvel Comics, of all companies!) The story and dialogue are extracted almost verbatim from Baum's original book, and then lushly visualized with some seriously fantastic art from Skottie Young and colourist Jean-Francois Beaulieu. It's a fantastic match of authors and material, if I have ever seen one!
The same team is already knee deep in adapting the sequel, "Marvelous Land of Oz." I don't know if they're actually planning on doing the entire Oz series -- that would be a pretty enormous project, after all -- but the series certainly seems to be in the best possible hands.