Does Google Audit all apps that enter the market place? Possible Duplicate:
  Are the apps safe? How can I make my Android more secure?  




There are several 'requires root' apps in the market and one of the most famous ones have more than 5 Million downloads as of date. We all know that an app that uses root privileges has the ability to do anything that it wants to. 
Google Play is supposed to be a trusted source. Does this mean that these Apps are audited before it is put on the Play store ? Or, is it possible that some of these rooted apps does something malicious in the background ? I've never uploaded an app to the play store and hence I do not know the process.
Yes.  Google uses a system they call "Bouncer" which automatically analyzes apps submitted to the store for malicious behavior.

A bit more information can be found here.

The system isn't foolproof though.  For example, in July, A few apps on the store were discovered to be downloading malware after the fact from outside the play store.