According to Apple iOS 4.2 is Coming Soon
The email says that iOS 4.2 will soon be in the hands of millions of customers all around the world.
The email was sent From developers to let them know they can now submit updated apps to the app store that contain 4.2 optimised code and then suggest that developers can start utilising Multitasking as well as Game Center (4.1 onwards) and finally AirPrint (iOS 4.2 onwards).
There still is no official release date for iOS 4.2.
this week or early next week as the final date when it will publicly become available soon. we will come soon with more details about it.