Adding to shot placement, I'd like to mention that a good bullet and cartridge can give you a bit of "wiggle room" if you happen to be off a couple inches.
I prefer the center neck shot, especially if I'm about to engage a large boar or a sounder of hogs. Unfortunately, my aim has been a little less than stellar on a few of my last hunts. However, the cartridge/bullet combo I'm using has killed every hog ive hit with an opening blast...even if I've missed the spine by nearly two inches (my very last hunt where I slid in a cow pile as I pulled the trigger not included).
This is where bringing enough gun is important. I've killed some huge boars lights out DRT with a .223, but placement and bullet construction are much more critical. You'll also lose more hit runners with a lighter caliber.
Todd's video is old...but the information is still spot on.