OK, so first of all, line of sight still exists, but you now shoot and resolve each weapon type in your unit separately. Most stuff here is the same as it was, including snap shot firing making you BS1. There is an out of range rule, where you can only kill what is in range, but it says that if you are shooting guns like rapid fire, you use the full distance when it comes to their killing range and removing causalities.
The closest models die as normal, and the book briefly states here that most cover saves are 5+. It also says that units that have gone to ground can no longer snap shot in overwatch. The focus fire rule is also missing!
Surprisingly, next up is not the assault phase, as the weapons pages have been moved to the next spot