But can they do it?
They've never developed an entire OS.
Android was bought in and deliberately used Linux kernel and a form of Desktop Java to leverage the Mobile Java developers on S60 etc. Sun wouldn't licence full Java for Mobile, at least least not free like desktop.
The Android GUI has little changed since Google bought it and the OS is still like a work in progress.
ChromeOS is the attempt to use only Cloud/Browser on top of Linux.
Also will it suit users and purely local processing or somehow be crippled without always on Internet, Cloud and a Google Account with Google tracking.
I'm sceptical. What have they ever developed apart from search?
Look at their attitude to law and privacy, stuff always in beta or abandoned.
Do they make MS look trustworthy?