To manually update, Mac users should close COD4 if it is open and then download mc002301
Then use Finder to move mc002301into the pb/dll folder inside the COD4 application (you may have to right-click the COD4 icon and "Show Package Contents" in Finder to browse through to "pb" and then "dll").
Supply drops--random loot drops first introduced in Call of Duty: Advanced Warfare--return, and are purchasable with Depot Credits, which can be earned in game, or Call of Duty Points, which are bought using real money.
Raven Software has announced that they will be updating the Sniper Collateral Damage in Modern Warfare Remastered in the next patch update.
Players have been asking for this update since launch, as many users have claimed the collat damage does not match the original Call of Duty 4 game.
New installments in the mainline series, however, have been released simultaneously, so this would be a change of form, in a way.
Bear in mind that none of this is confirmed at this stage.