Although the latest Call of Duty: Black Ops 4 update has plenty of stability fixes and a few content-related additions, Treyarch revealed that it's merely setting the stage for next week's big update, hence the sizeable footprint.
The Call of Duty: Black Ops 4 update apparently weighs in at 14GB for PlayStation 4 users while Xbox One players had to download 22GB. The game's PC update is due today, along with some PC-specific changes.
Treyarch wrote that the 1.08 "update is all about gameplay and stability improvements across all three modes, as [they] set the stage for an even bigger update next week."
It seems that a brunt of these big changes is reserved for Blackout though, as Treyarch have "an extensive set of features, events, and more surprises planned for the future of Blackout." They will reveal more in a dedicated post later on though.
As for Call of Duty: Black Ops 4's 1.08 update, Treyarch added calling card, emblem and echelon info to player HUDs and killcams. Zombies Origins Character Missions and the Blightfather event are coming to Xbox One and PC today as well.
Black Ops 4's multiplayer received spawn tweaks for Hardpoint on Seaside and Hacienda. Also listed was a host of crash fixes that are too long to list. Care package landing physics has been improved and they won't be getting "stuck and being flung off the map".
Hellstorm's could apparently lock onto targets that were "under roofs and not reachable by the missile", which Treyarch addressed in Call of Duty: Black Ops 4's 1.08 update. The team also tweaked a few challenges, namely the 100 Percenter, Bring the Pain and Got Rocks, which should unlock and track properly from now on.
Treyarch already revealed that Blackout won't be getting new maps anytime soon since the company would rather iterate on the existing map, so that's one thing we can scratch off the list of potential changes.
You can find Call of Duty: Black Ops 4 1.08 patch notes here.