As much as I wanted to really enjoy Pragmatic VC Using Git it fell short of expectations set by the unusually high quality of the free/cheaper offerings.
The Peepcode Git Internals PDF, as mentioned before, does a much better job explaining Git and appropriately setting your mental model of how to work with Git.
I really can't fault the Swicegood book much though. It accomplishes what it set out to do: teach a user version control using git. If you've read the other books in this same series you're not going to learn a lot.
Unfortunately, even new-comers are probably better served learning Git for what it is, not as "a version control system like subversion and cvs but..." Most of the other git tutorials adopt this stance. While it may be somewhat off-putting if you're really not interested in the technical details or guiding philosophies and just want to get to work in the long run you're better served.
So bottom line, I'd pass on the Swicegood book, it may be worth reading, but probably not worth owning as you're not really going to refer back to it often.