Chromebooks quickly took the place of Android tablets, though it is not quite ready to replace your mac or PC, it will definitely get the job done. I find myself doing more typing and working on my Chromebook now then my macbook. Although it lacks some of the production apps that I turn to my macbook for it makes up for it with its lightweight operating system that makes booting up and getting around the system smooth and fast.
So with an operating system this good why would it not be ready for an enjoyable tablet system, because of the apps. Google have been experimenting with Google apps on the Chromebook for over a year now, and they are still experiencing issues. Though all of it is not their fault that app developers have failed to optimize their apps, at the end of the day customers are going to blame Google for not having enough optimized apps for the tablet experience versus the app developers.
There have been several rumors posted about Google working on another OS to truly bridge the desktop and phone operating systems as well as be able to be used on any device. Though I am not expecting Google to rush an unfinished software to market, ChromeOS needs to be further along with android apps before being a device for tablets. Also it would help if instead of duplicate apps, there was an option in the app itself to switch from tablet to desktop mode (android app to chrome app).
ChromeOS is continuing to grow and improve to the point I highly recommend chromebooks, but I am curious how well this will be received as a tablet.