The tendency is to prioritize the release of open data sets based on the needs and the values of the community of users. That implies a big effort made by governments right now to better understand the demand, meaning to engage with the various groups of actors, which is not an easy task, but they're moving towards that direction.
We are seeing a new level of sophistication. The governments may have started with opening as much as possible, and now they are becoming more targeted in prioritizing which data sets to release.