Apple on Friday posted a pre-release version of OS X Mavericks 10.9.1. The new release is available for download only if you're a registered Mac developer; it's available through Apple's developer web site.
OS X Mavericks has gone Golden Master and we're expecting to be released later this month, perhaps around the Apple event scheduled for next week. In the interim, Apple has put the word out to registered developers to get their apps ready for the new operating system.
Apple's newly renamed iOS Developer News feed has released two notes today, one on exciting new features in iTunes connect, and the other announcing iAd for Developers -- a great way to promote apps, in apps.