It's funny how often Google will make a change to their services or products and not bother to tell anyone about it, or will wait for sometime to do so. The latest example is that there is a new content approval rating system in place for the apps on the Google Play Store. It has apparently been in place for several weeks. The new rating systems match the respective country/region they are in, thus you will see the familiar ESRB in the US, and PEGI system in Europe, etc.
On top of this, Google also announced that they actually have a team of Googlers in place who manually approve the apps. This is another big shocker as this is something Google seemed to shy away from for years.
You can check out the full details at the source link here: Creating Better User Experiences on Google Play Android Developers Blog