Hickory or mesquite? Personally, I prefer mesquite over hickory. Apple, cherry, and pecan wood is nice, but sometimes not that easy to find for a reasonable price.
After marinating, with your wood smoking white, put the cape-side (fat side) up away from the direct heat (put it under the vent so that the smoke has to go through the meat) Do not buy a brisket that has no fat. Believe it or not, the fat is important on a brisket. And the cape-side is always on top.
Allow 30 minutes for every pound of brisket cooking time, then smoke it to your liking.
To make sure you have the correct cooking temperature in your grill/smoker, test it by putting your hand (one-inch) over the grill. If you can maintain it for at least five seconds, you're at cooking temperature.
This I do, and I average about a 15-16 pound brisket. It's on the smoker for 9 hours.
And remember, if you can stick a fork in the brisket and simply lift it off the grill, it's no good. Why? Because it ain't tender enough. If you do it right, you will need spatulas (large) and/or a flat pan to get it off the grill.
I'm even better with ribs. But that's for another time.
Enjoy!