For anyone who hasn't seen the show, this book is probably not a good introduction, as it throws you straight into the story, without giving any kind of background. For those who have seen the show, however, this does not pose a problem.
Whereas the Doctor Who book I recently read felt like a TV episode, this has a longer feel to it. Running alongside the main story are other smaller storylines. In the TV show, Torchwood deal with one neat story every week, but this book has a more realistic feel to it, as they go from one problem to another.
The characters were fairly well captured, as I found it quite easy to picture them. However, Ianto plays a very small part, and Jack doesn't feel quite right.. he seemed more `relaxed' than I remember him in the first series, plus the leadership skills aren't that apparent.
A rather confusing factor is the introduction of a new character, James.. but bear with it, as it does all make sense at the end.
The actual book is a fast paced read, it hooks you in, and keeps you turning those pages. Highly recommended for fans, and I'm certainly hoping to pick up some more!