I just left a review for Fable Hunters, a similar product from the same company, so forgive me if I save some typing time by repeating a few comments.
In 20 odd pages, Vigilantes gives you the skeleton of a modern dark heroes campaign where crime and corruption are running rampant, and a few angry men and women have chosen to fight back. The book provides a brief background, some stat-less archetypes (and as the other reviewer said for Fable Hunters, some stats would be nice) for players, some new edges and flaws, and stats for the bad guys. I particularly like that the book includes a number of stereotypical bad guys, from biker gangs to ninjas to corrupt cops, so that a campaign can have some decent variety of adventures.
I personally am I big fan of the random adventure generators you get in many Savage Worlds games, and this has a good one, but one that I would have liked to have been a bit larger with more entries. At a mere d6 per adventure element, I can see a lot of duplication happening.
Between this and Fable Hunters, I am a fan of this company and this line of products, and will definitely keep my eye out for more campaign setting kits.