Albeit, I'm biased--a long time Anne McCaffrey fan, and I've corresponded a few times with Elizabeth Ann Scarborough. But for all I'm loyal to Pern, Pern has *nothing* on this one.
Petaybee is a world without equal--both in climate, its own special 'personality', and in the characterization of its people. From charming Sean Shongili to helpful Bunny to the single-minded determination of Torkel, each character is different and unique. And no super-heroes either--even Yanaba makes mistakes.
Of course, there are minor problems. The affectionately dubbed 'Anne-science' shows up in this book, too... but only skeptics can allow that to interfere with the story. Personally, I don't care just how they managed to make humans able to tolerate that climate... what matters to the story is that they *did*.
The characters aren't limited to humans, either. Although only in bit parts, cats, dogs, and a breed of long-haired horses called 'curlies' play important roles, making this book good for any animal-lover. But those are all *common* animals... want something more exotic? How about seals? And if that's not enough, check out the unicorn on the cover.
All in all, Powers That Be falls in its own category of science fiction. The science is dubious, but the fiction more than makes up for it.