General info: Mango, or the “forthcoming release of Windows Phone,” will provide developers with more hardware capabilities, better browsing and improved tooling, and expanded opportunities and Windows Phone Marketplace options.
New tools. In May, Microsoft will release a (beta version of) a new set of developer tools that will help developers create Windows Phone apps that are even faster, more capable, and better integrated with Windows Phone.
Application multitasking for background processing, audio and file transfer, and fast application switching.
Deeper phone integration. Vague, but will include new Live Tiles capabilities.
Camera and motion sensor access. Developers can build apps that work with the device hardware.
Internet Explorer 9 with HTML 5 and standards support, and hardware acceleration.
Also, there are going to be some new app demos today include Skype, Spotify, Layar, Qantas, Amazon Shopping, and Kik Messenger.
Oh, and this: