My Nexus 7 finally got the Android 4.3 update, just about one week after Google said it was released.
From AnandTech:
One of the common complaints late in the life of the original Nexus 7 was slow storage I/O performance, leading to an inconsistent user experience. After a fresh flash, the Nexus 7 was speedy and performant, but after months of installing applications and using the tablet, things began slowing down. This was a friction point that many hoped would be fixed in the new Nexus 7 (2013) model, which it was. There’s even more to the story though, it turns out Google has fixed that storage I/O aging problem on all Nexus devices with the Android 4.3 update.
You dont’ have to read between the lines that prior to Android 4.3 Nexus 7 had a serious flaw.