Microsoft states that this update contains their usual scope of fixes and improvements, in addition to providing several required update for continued future testing of the Microsoft update systems. The update will deploy to each device as a "critical update". The mandatory update will provide the device with the latest build offered for the Windows Phone Preview, in the Developers available downloads. In addition, ignoring the update will cause the update to automatically install 72 hours after it has been downloaded, or you can install it right away. Continue reading this article here.