Expression Blend 4 SP1 includes support for building Windows Phone 7 apps and improved integration with Adobe design tools through support for FXG file format, as well as bug fixes and stability enhancements.
Windows Phone support. When you install Windows Phone Development Tools, you can use design tools in Blend to create WP apps, including WinP project and item templates, graphics and animation tools, behaviors, and sample data. Once you've created WP app, you can build it and then preview it either in WP emulatoror in a WP device attached to your computer.
Adobe FXG support. With Blend Add-in for FXG Import, available when you install Blend 4 SP1, you can add FXG 2.0 symbols as UserControls in Blend. You can also configure FXG settings so that when FXG files are updated outside of Blend, the files you've added to Blend are also updated.
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