Android Application RatingGoogle is introducing an application content rating and filtering system
for Android Market.  This has been a highly requested feature from both
users and developers.  Android Market Content Policy remains the same.
 We are introducing four levels of content ratings:
- All
- Pre-teen
- Teen
- Mature
Details on how to rate your application can be found in the Android Market Help Center here:

Starting on November 30th, 2010, it will be mandatory that you add a rating level to your apps in the Developer Console at when you publish or update an app.

The Android Market will be launching the content ratings to end-users starting in a few
weeks. At that time, existing applications left unrated will be treated
as “Mature” to ensure an appropriate user experience. This means that
unrated apps may not be viewable to many users depending on their
setting, so we encourage you to rate your app as soon as possible.

Time to go and update your existing apps and classify/rate you new apps. All the best.