This release has stable support for WPF, Silverlight for Desktop and Silverlight for Windows Phone 7.
Attention: on Windows Phone 7, for performance reason, virtualization is an opt-in feature. If you plan to use the FlowItemsControl2D / 3D for many items with very simple item templates, make sure to change the ItemsPanelTemplate to the virtualized version.
Attention: on Silverlight for Desktop, you can obtain better performance by enabling GPU-based composition.