A paper on the architecture of Windows 7 comes Phone filter and gives details on the latest mobile operating system from Redmond.

Phone Windows 7 is a 32-bit operating system with dual-layer architecture, the first being reserved for the kernel while the second is for the user. Applications use virtual memory to 1 GB and 2 GB are used by the processor users. The kernel uses for its 2 GB of memory.

Microsoft provides the runtimes for 2D graphics and DirectX 10 and 11. It is also interesting to note that OEMs will be responsible for developing and distributing the drivers of the graphics chip and not the publisher of Redmond. Windows OS 7 Phone also uses two different file systems. The IMGFS is intended for system files and TexFAT is reserved for the user who can store files on memory card or internal memory.

Apparently, according to documents, files critical for the proper functioning of the text lies in the user layer of the OS, which means that if the memory card is removed or when the data were deleted, the phone will be useless and not set up as emergency calls.

Phone as said by Microsoft
The updated operating system or the operator will go through the Microsoft Update and it will be possible to download using the 3G network or the Zune software installed on the PC.

Windows Phone based on Windows Live ID to coordinate data with Microsoft's servers and access Marketplace, similar of iTunes Store. Further than that, nothing outstanding. Bing will be default search engine; operators can change startup screen with titles on homepage of phone. A ROM host up to six third-party applications to send them directly to phone. This area must be utilized primarily by operators.