If you were expecting that then you were expecting too much from PA anyway to be honest. PA only adds a few things but it doesn't really touch what's already in the Codex.
Wat? Literally every single SM faction, be it DA, BA, or SW, got Vanguard sheets in PA books. DW not getting it is
exception to this rule. Unless you call adding extra 20+ pages "not touching" 
Especially seeing they could just print Vanguard kill team instead of 5 separate units, thus saving space...
Theoretically:
- Combat Doctrines added
- New Warlord Traits
- New Stratagems (confirmed - most likely includes the ones from C:SM that all SM armies have gotten so far).
- New Litanies (confirmed - either the ones from C:SM and one extra; like C:BA, C:DA, and C:SW, or unique like C:GK)
- Addition of new units; Incursors, Infiltrators, Suppressors, Phobos characters, Impulsor, etc.
With all that, I don't think one new/updated unit profile for Primaris Kill-Teams is that much. Infiltrator could give 12" deployment denial , Incursor could give access to haywire mine, and Suppressor's utility comes from the weapon.
DW is getting 5 pages. Seeing every other marine PA book wasted 2 pages on various chaplain entries to give them litanies, DW will do it too. That leaves 3 pages, one for stratagems, one for litanies, one for doctrine. Seeing all three sources previewing WD didn't mention warlord traits, superdoctines, relics, psychic powers, or extra units/rules, I wouldn't be holding my breath waiting for those.