Shanower's actually been an Oz creator for many years: he's scripted and drawn original Oz graphic novels, and he's written and illustrated several brand new Oz novels in the manner of Baum but in his own inimitable style, continuing the adventures told by each generation's Royal Historian of Oz. (I highly recommend Paradox in Oz by Edward Einhorn with illustrations by Shanowerit's basically Crisis on Infinite Ozes, with a wonderful two-page illustration of Ozma encountering every other version of her Her Royal Self throughout reality!
And speaking of other Ozian realities, check out this cartoon by Eric Shanower from the beautiful and very-much-missed Oz journal Oz-story. It's a piece that asks the musical question (altho' not to the tune of "Over the Rainbow") "What If...Comics' Biggest Names Drew Oz?" How about it...how many can you guess? (aw, c'mon, take a guess!)
"If Six Cartoonists Had Drawn Oz Comics!" by Eric Shanower from Oz-story #2 (May 1996)
Leave your answers and guesses in the comments; don't cheat by looking at anyone else's comments, and remember, there is no money in Oz, so no wagering!