I received my replacement Google Nexus 7 tablet to replace my dead one I returned earlier this week. It had base Android 4.1 Jelly Bean on it. I knew that Android 4.1.2 shipped earlier this week, so I checked for updates.
It only offered the 4.1.1 update, so I downloaded it, restarted and applied the update and then I had to run a second update to get to 4.1.2, which when required another restart to apply the update.
No combo update for a consumer product released in 2012, this is hard to believe. While Jelly Bean is far better than any other version of Android, it is still behind and missing some of the key consumer user basics.