I have read few pages of Alan Hohn's introductory git online book and i appreciate it it's a good work but i stop, time is precious (maybe i return when i get more experience) :) ; i don' t feel recommend it to newcomers why?
IMHO The Alan's decision to do parallelisms with SVN is wrong because put confusion in a subject tough per se. Better examine git on his own because actually is on his own in the field and has his own mind set.
Dunno if Alan' course is proficient for people that comes from SVN(i have my doubts cause the different mindset) but definitely it's not recommended for practitioners only because of SVN's references.
PS: I am not a git addictive but simply describe my (till now little) experience For newcomers or who has no time (as me actually) to study git but need work with the small 2 books bellow in that order beat the target
1. Git Succinctly by Ryan Hodson 2. Git Internals by Scott Chacon