Apple released OS X Mavericks 10.9.1 in two flavours being Build 13B42 (243.4 MB) and Build 13B3116 (364.1 MB):
The important thing that you might want to know is that the latter upgrade includes not only a lot more files, including a lot of graphics related kexts, but it also includes later revisions of the files. For example. AppleHDA.kext from the first link is v2.5.3 but the one from the second link is v2.5.8
Also. The mach_kernel is not included with the first one and it lacks updates to XCPM like IOPlatformPluginFamily.kexts where resource files in X86PlatformPlugin.kext are being replaced/added:
Mac-2BD1B31983FE1663.plist – MacBookPro11,3
Mac-3CBD00234E554E41.plist – MacBookPro11,2
Mac-7DF21CB3ED6977E5.plist – MacBookAir6,2
Mac-F60DEB81FF30ACF6.plist – MacPro6,1
A bit odd maybe is that it also includes a fix for the MacBook Air to remedy this message in var/log/system.log
--> Network delay is not specified! Defaulting to 0x384
As in Apple finally added this snippet:
Meaning that you yourself won’t have to edit the kext anymore. Which is great of course. Thanks Apple😉
It also included the latest plist for the new Mac Pro, which I assume is something people using the new Mac Pro SMBIOS would want to have. But no. The About This Mac image is not included with these upgrades.
And remember this tip. You can download the files by following this link: https://swscan.apple.com/content/catalogs/others/index-10.9seed-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
People who want to install this update should use a SMBIOS from the late 2013 MacBookPro11,n which can be found here but please make a backup first! Before launching the installer. You know. Just in case you run into a problem. Also note that the installer will fail on Build 13A2093 and 13B3116 (as it should).
p.s. Some people are looking for a combo update, but there is no combo update for the first update to OS X as there is nothing to put together (combine).