In addition to iOS 7.1.2, Apple today released OS X version 10.9.4 for all Macs running Mavericks. While 10.9.3 was a relatively large update that improved 4K display support on several Macs and restored local contact and calendar syncing, 10.9.4 is only a few hundred megabytes and focuses on smaller problems.
Apple's official release notes indicate that the update resolves a problem some Macs had with re-joining known Wi-Fi networks, makes wake-from-sleep more reliable, and solves a problem where the Apple logo wouldn't display correctly at boot. The update also includes Safari 7.0.5.
The small size and scope of this upgrade is probably attributable to the work the OS X team is doing on OS X 10.10 Yosemite, the major release that is due in the fall. Yosemite completely redesigns the interface to bring it more in line with iOS 7 and introduces a number of features that make OS X and iOS devices work better together.