In the greater history of computer gaming, Linux is a relative newcomer, still missing out on quite a few AAA titles and only recently gaining access to Steam. While the library of games is growing for the open-sourced OS, the actual development process is still locked in to Windows. Most of the tools used for designing 3D models (e.g. Blender), landscapes, and other graphics have made the transition to Linux, but the primary coding tools are mysteriously absent.
A little bit of connecting the dots has revealed that Qualcomm is the reason behind the new Nexus 7's lack of factory image / driver binary support. This has long-time AOSP maintainer Jean-Baptiste Quéru pretty upset. Upset enough that he is "quitting AOSP."
It's not clear if this means JBQ is quitting his job at Google (though the fact that he even wrote this kind of suggests he may be quitting / has quit), or that he's moving to a different part of the company / Android group.
Update: Looks like we were right.
ROM developers and Android tinkering enthusiasts alike have probably noticed at this point that the new iteration of the Nexus 7, unveiled two weeks ago, does not yet have factory images or driver binaries posted on the appropriate Google Developers page. A similar issue plagued the Nexus 4 in its early days, though eventually images were posted. At the time, legal issues were speculated as a possible reason for the delay, and Android build maintainer JBQ - largely responsible for the images / binaries - said only this in response: "I can't comment."
With the new Nexus 7, JBQ has not outright said that legal problems with Qualcomm are preventing the factory images (and possibly the driver binaries) from being published, but a quick look at the relevant evidence makes it pretty duh-obvious that's what's going on.
Just like last year, the Google I/O app's source code has been released in an effort to get developers acquainted with Android best practices.
In a post to Google+ today, the Android Developers page outlined some of the things the source code has in store for those curious. Among them are techniques to implement responsive design across phones and tablets, use content providers and implicit intents in app navigation, using sync adapters to provide new content "in a battery-friendly way" and loads more.
So, you want to know about everything that's new in Android 4.3. Every single change that's occurred since 4.2.2. Well, if you don't mind scrolling through a barely-human-readable, mile-long developer changelog, now you can satisfy that urge.
Al Sutton has posted a wonderfully-formatted AOSP commit changelog covering the changes from Android 4.2.2 (JDQ39) to Android 4.3_r2.1 (JSS15J). The JSS15J build is the most recent release of 4.3, and is the one currently shipping on the new Nexus 7.
If you've already updated to Android 4.3, whether via an OTA or by flashing it manually, and rooted it, you're more than likely using Chainfire's SuperSU, which carefully works around the new restrictions Google put in place. Cody has a good write-up about why they did it and what's going on, so go read that if you're interested in the details.
Chainfire created the Android 4.3-compatible root method and the updated SuperSU back when the first leaks showed up for the Galaxy S4 but hasn't updated it for a few weeks.
Google has made a small change to the Google Calendar API that nonetheless could make a huge difference for developers and users. The Calendar API now supports push notifications - alerts sent directly to devices and apps instead of waiting for a client-side sync, a la Gmail - for updates that are practically instantaneous. The official app has had this for a while, but now third-party developers have access to this functionality, meaning that push notifications for subscribed Google Calendars can be sent to any app that supports the general Gcal API.