Google posted on their Android Google+ page that the Nexus 7 Wi-Fi (2012 and 2013) and Nexus 10 can now be updated to Andorid 4.4 KitKat, if you so desire. It also stated that the Nexus 7 Cellular (presumably also 2012 and 2013) and Nexus 4 will get the KitKat update soon. The Nexus 5 was the release device for the new operating system but has been the only device with the OS until now. One of the benefits of Nexus devices compared to third party devices are fairly quick OS updates. It's still not as quick as Apple who releases the newest iOS update for all compatible devices at the same time. It's only been about two weeks since the Nexus 5 was released so that's still not bad. I remember with my Asus Transformer TF101 it took a couple months for it to get the newest OS. Google's main push for KitKat has been it's ablility to run on less powerful hardware that was previously only able to run Android 2.3. This would make low end tablets and smartphones a lot more usuable. It would also allow developers to be able to focus more on app features and support for the latest OS rather than have to keep supporting a legacy operating system like 2.3. See Google's Android KitKat page for more information on the changes and features of the OS.