Jeanette Winterson has written some of my favorite books. She's daring, experimental, and tackles difficult themes bravely. Sometimes that works exquisitely (which is how I feel about some of my favourite books of hers, such as Oranges (obviously), Art & Lies or Lighthouse Keeping)... here it does not.
The Powerbook was frustrating because I felt it had potential but instead read like a disappointing companion to sexing the cherry, which I also didn't care for. It's not irredeemable and I can see what she was going for, but it's not for me.