Yeah. It's basically just kicking and punching in the air. I read the same book (really good, wasn't it?), and I tried it. It's really good for just loosening up, letting yourself flow (which is good for me, because I tend to think too much about what I'm doing instead of just letting it flow through me), and provides a moderately good cardio exercise (depending on how good of shape you're in, and how fast you shadow box). Hope this helped!
"If life gives you lemons, you blow those lemons to bits with your laser cannon!" - Brak