Google announced Android 4.3 Jelly Bean earlier today during the 'breakfast' event. While they detailed the changes that one can expect with this update and mentioned how the update would begin rolling out to Nexus devices today -- there is also another aspect. That other is the release of the factory images and it looks like they have recently landed on the Google Developers site.
These images are made available by way of the Android Open Source Project (AOSP) and mean users will be able to download the factory images. Basically, these images are the way the device would be as new. And while we wouldn't necessarily suggest taking this route, these images could be used to wipe and update your Nexus device.
That thought aside, the Google Developers site has images listed for most of the newer Nexus devices. The images are available as JWR66V and for the Nexus 10, Nexus 7 (WiFi), Nexus 7 (cellular) and Nexus 4. There is also a few builds available for the Galaxy Nexus (GSM/HSPA+). The Galaxy Nexus builds include one with, and one without Google Wallet.
While Google took care of the GSM/HSPA+ Galaxy Nexus, we should clarify that this does not include the Verizon CDMA model. That handset is still listed, however the newest version available is Android 4.2.2. With that, while these are available and while they can be used to update your device -- it will probably be easiest for most users to have some patience and wait for the over-the-air update to arrive.
SOURCE: Google Developers