The updated Chapter Tactics for the Space Marines were revealed on Warhammer Community yesterday. I had a look at the new traits for the Marines and am very excited by what this might mean for the codex.
First off, it appears that vehicles will now be getting access to the Chapter Tactics as well from now on. This will be a nice boost for them, as most other armies' vehicles were getting access to their own version, so it's nice to see Marines brought up to date with this. This will give some of them a nice boost to their firepower and durability.
The Ultramarines Chapter Tactic was pretty much unchanged. As it was arguably one of the best in the old codex, this isn't too bad. What is a big change is that vehicles will now benefit from being able to fall back and still shoot. This is a big boost for many tough vehicles such as Predators or Land Raiders, as they will still be able to put out a decent level of firepower when falling back from combat. It will also be even harder to shut down their firepower, as you will need to surround them and stop them from falling back to block their firepower completely.