The first two rulebooks have AWESOME fluff and info on the models. Sone of the rules for the models have been updated via new stat cards (wjich you can download for free) to blance and clarify rules. The rulebooks have also been errata'd to clarify and tweak rules fora fairer and more fluid game.
Instead of releasing just an errata, they released the rules manual which has all the updated rules in it. You can buy it (the cost effective rulebook
Cubert mentioned), which is of brilliant quality, or you can downliad it free. The cards are fantastic too, but you can opt to use normal playing cards so its cheaper.
In addition, if there is a rules query that needs clarification, there are rules marshals on the forum who can give you a definitive answer in good time.
Basically, Wyrd looks after its community. Malifaux, as a game, and as a story, far outdoes whfb and whormachine (for me), and 40k gamewise and is on par fluffwise. Its also got great models and great prices (in comparison at the very least).
The gameplay can move very quickly when you get the gist of your crew and rules, and is very tactical, as you have your main strategy and then schemes which can be kept secret if you wish. This gives you around 6 objectives to think about - completing youre own and preventing your opponent from completing theirs/guessing their schemes. Each player takes turns to use one model at a time which can either go for objectives, charge, shoot, move to protect themselves or more important models, get in the way, or set up combos. This creates a game where forward thinking is king (think chess, in a sense). As ratty said you have a hand which you can use to improve on the cards you flip for attacks/spells etc., but you have a limited amount. This means you have resource management to think about. Masters can use soulstones, which generally makes them more powerful than other models, but is another resource to use wisely.
This game is Fried Gold, and is pretty easy to pick up after a couple of games. Its not all kill, in fact you can lose every model and win, and is characterful and different. I dont think you will be disappointed with this game.
...ill stop brown-nosing now :$