Android Malware - out of context or out of control? Of the 51,000 apps that F-Secure reported as being Malware at the end of 2012, only 146 were from Google's Play store and of those 146, only a small percentage of that were considered serious.
SO, out of 800,000 apps in the play store, roughly 50 were considered serious Malware (as in designed to steal info of a personal nature, not something lame like dial or text high cost sex centers and the like). That means you have a .0000625% chance of getting malware from the Play Store. Additionally, Android 4.2.x now scans apps that are side loaded, helping to stop malware from getting on your phone.
Of course, if you are in China and dl apps from nefarious non-Google sources and do a lot of side loading, then you are at serious risk. This is why we never here of infections by "real" users of Android in the US and Europe.