How closely does this blurb match the actual plot of the book:
From the Back Cover
" ... Tim Powers is the apostle of gonzo history, and On Stranger Tides is as good as story-telling ever gets. He has found a way to bring together powerful Indian magic, black vodun, a British scientist driven mad with grief over his wife’s death, and Blackbeard himself, determined to live forever. Opposing them all is John Chandagnac, a one-time puppeteer who has come to the Caribbean to confront the uncle who cheated John’s father out of his rightful inheritance. Captured by pirates, John finds himself rechristened Jack Shandy; he also finds that his old skill as a puppeteer can save his life.
Because honestly, aside from the setting and the use of "Indian magic," it doesn't seem all that similar, beyond the general similarity to be expected of any fantastical pirate yarn set in the Caribbean. Even the theme of immortality is rather strikingly different; Blackbeard craves it, whereas Barbosa et al fought bitterly to be free of it.
" ... Powers writes in a clean, elegant style that illuminates without slowing down the tale. The story promises marvels and horrors, and delivers them all. You’ll love the characters, you’ll stay awake all night reading it, and when you finally do sleep, you’ll find this story playing through your dreams." — Orson Scott Card, from Hatrack.com
Oh, boy. If it gets Orson's approval, then I really have to wonder about it...
Granted, these are impressions formed without having read the book, but it seems to me that while a vague similarity is present, it's not sufficient for Powers to sue Disney about it. Heck, the first five customer reviews don't even mention the Disney film, so the likeness can't be too overwhelming, can it?