I'm currently reading it. It gives a rather basic C introduction (I skipped it) but then it goes into explaining how to inject shell codes, using buffer overflows and getting deep into the assembly of programs. It's definitely great for a start.
I'm reading it now, too. There are a lot of examples (it comes with a VM), but the book is still more conceptual than hands-on. The exploit-exercises site posted above looks pretty good.
