So far, I don't see any glaring errors or misleading lessons. As a matter of fact, she quickly enforces the -wT flags and talks of security in the very beginning, making the right impression on the would-be Perl Hacker. I also find the flow and approach extremely easy and empathic - I wish I had such a book when I was first starting out.
I'm only around page 50 or so, so I haven't finished it to give it a thorough review yet, but as it stands now, it would be a book I recommend to beginners.
On the flip side, the book doesn't enforce 'use strict' as strongly as I would like - imo, it should be suggested very strongly and that non-compliance can lead to mockery from experts when approached for help (you try asking for help when you mis-spelled $frist/$first or something to that effect). Of course, I leave that to Liz to dress-up better.