Although James Tisdall's Perl books (Beginning/Mastering Perl for Bioinformatics) could be a little scattered, I found that they offered more for the biologist learning Perl than this one; you could almost buy both those books for the price of this one! This book seems structured more along the lines of the (superior) Learning Perl and Intermediate Perl by Schwartz et al, with a few biological references thrown in as examples. Some of the most important aspects of biological sequence analysis were glossed over fairly quickly if at all. I found it somewhat amazing that file format parsing, restriction enzyme analysis, sequence conversion, transcription-translation, program output parsing, and other fundamental topics were either covered very briefly in passing or not covered at all. Disappointing!
I believe one might find this book was a great read first time out (it is well written), but that once they progressed to other texts (Learning Perl, Intermediate Perl, Programming Perl), they would rarely, if ever, refer back to this one. That's not good for a $50 book. I can't see myself using it in the future when I have the Camel and Llama covering my back, along with Tisdall's texts. Basically a lot of sugar coating without much substance.
Oh, and there's a major mistake in the Object-Oriented Programming section, one which really breaks your programs. In short : -> != =>
My advice: spend your money on those texts and use your imagination on what Perl can accomplish for you as a biologist. If you are an advanced Perl programmer and biologist, at least check out Tisdall's books and wait for the long-rumored BioPerl book. I would give it 3 stars for the writing but the price doesn't justify it, sorry. The Amazon review system won't let me change the rating though, so you lucked out this time!