RE-READ UPDATE: Same thoughts as below; wildly inventive (at least until everyone reaches Oz), but totally pointless/plotless throughout.
Shanower does a nice adaptation of Baum's original story (such as it is), but the true stars here remain illustrator Skottie Young and his colorist Jean-Francois Beaulieu, (who deserves equal credit to Young, and who also teamed up with him for his delightful — and delightfully perverse — "I Hate Fairyland" series), as literally every panel is a fine art masterpiece. Cannot recommend more highly, at least from an aesthetic POV.
ORIGINAL REVIEW: The weakest link in the saga so far, as there is no real plot per se. Dorothy, Zeb and the Wizard find themselves back in...well, I'm not sure where exactly; somewhere deep inside the Earth, after which the whole book is them just trying to get from there to Oz and then once again from Oz back home again.
But Baum's mind-blowing creativity is again on full display, backed up once more by Young's delightful illustrations...so still hard to give this less than 3.5 stars. And it's not just Baum's imagination that amazes me — it's the sheer randomness of it; I have no idea how he came up with all these unrelated incidents and characters without doing massive amounts of drugs: the plant-based Mangaboos; the invisible denizens of Voe who are preyed upon by invisible bears; the bizarre Braided Man who forces on them boxes of rustles and flutters (which are never heard of again); the cave-dwelling dragons who are waiting for their mother to return (again, never mentioned again); the wooden Gurgles with their detachable wings...it's just wild and mesmerizing, if ultimately somewhat pointless.
I don't know what it is, but it seems that every half-century or so, the world is treated to one of these legends of what is apparently called Portal Fantasy. First, there was Lewis Carroll in the 1850's; then Baum in 1900; and next C.S. Lewis launching the Narnia chronicles in 1950, (as well as Norman Juster's amazing 1961 one-off, The Phantom Tollbooth).
So who then came next? Well, Harry Potter is the most famous late-20th century contender, but lacks a real "portal" element; so no — it ain't him. I'd probably have to go with Philip Pullman's His Dark Materials. Yes, the first book (and now also the fourth, disappointing "prequel" Le Belle Sauvage) are strictly "parallel universe fantasy — but then once Will comes along in Book Two, the rest of the series is pure "kids trapped in other worlds and trying to get home," and so fits the bill quite well. And Pullman certainly offers a comparable menagerie of spectacular characters and devices — daemons, armored bears, Specters, Gallivespians, Mulefas; alethiometers, subtle knives and amber spyglasses.
Finally, I have to add that I'm enjoying the Oz books more than I ever did the Wonderland or Narnia stories. Much of it is I'm sure due to Young's brilliant artwork — but I think I just like the "American-ness" of Baum's stories more than the so-very-British Alice and the Pevensie children. Solely a personal preference based on my own background, but there it is :)