And this is a great strategy. Google is simply bidding that being able to "own our data" will 1. someday be a hot legal issue 2. allows people to interoperate their data sets with other applications (that Google can then buy or learn from) 3. allows paranoid people to manually backup their own data 4. only a small fraction to move to another service or application, but only if you don't provide a better product yourself... 5. so to prevent that small fraction of users, they only need to be good... something they've been pretty good at so far, plus it gives them clear business goals : just be one step ahead of everyone else
By allowing people to export their data, it also allows them to make backups and to interoperate with other applications.
