With all the hubub with updates this month, Apple have given their OS a shakedown as well. Apple has recently released a large number of updates aimed at a variety of users.

Snow Leopard (10.6.x) Users:

Security Update 2010-003: Issues addressed include the recently discovered Zero Day vulnerabilities in Mac OS X and other security flaws.
6.50 MB download size

Max OS X 10.6.3 v1.1 Combo Update (Client & Server): The 10.6.3 v1.1 Update is recommended for all users running Mac OS X Snow Leopard and includes general operating system fixes that enhance the stability, compatibility, and security of your Mac/server.
785.29 MB download size (client update)
897.32 MB download size (server update)

Leopard (10.5.x) Users:

Security Update 2010-003 (10.5 Client):  Issues addressed include the recently discovered Zero Day vulnerabilities in Mac OS X and other security flaws.
218.6 MB download size

Security Update 2010-003 (10.5 Server): Issues addressed include the recently discovered Zero Day vulnerabilities in Mac OS X and other security flaws.
379.5 MB download size

Server Administrators:

Server Admin Tools 10.6.3: Updates to the following Applications and Utilites: iCal Server Utility, Podcast Composer, Server Admin, Server Monitor, Server Preferences, System Image Utility, Workgroup Manager, and Xgrid Admin.
236 MB download size

27″ iMac Users:

SMC Firmware Update 1.0: Resolves Target Display issues on the 27″ iMac
397 KB download size

EFI Firmware Update 1.0: Resolves high CPU-utilisation when playing audio via the audio jack and the backlight failing to power on after booting your Mac.
2.1 MB download size

So all you software-update junkies and security know-all alike, head on over to Software Update to download the latest and greatest from Apple.