An exciting addition to ArcGIS at 10.1 will be ArcGIS Runtime, which lets developers create and deploy focused, stand-alone GIS applications for desktop users, who have been asking for a small, lightweight deployment that, in terms of capabilities, fits between ArcGIS Engine and the ArcGIS Web Mapping APIs. The new runtime is designed for both desktop and cloud development. It has a fast display and does not require installation; it can be run directly from a CD. The learning curve for the new runtime is expected to be very gentle for developers familiar with the web APIs.