Silverlight 2 Beta2 includes a bunch of work in the data space:

DataGrid

Beta2 adds a number of new features to the DataGrid control. These include:

·         Auto-sizing support for columns and rows

·         Column sorting (with both single column and multi-column sort support) 

·         Column re-ordering support by end-users (allowing them to drag/drop columns to re-arrange the order)

·         Frozen column support (allowing you to prevent a particular column from being customized)

·         Performance and bug fixes

DataBinding

Beta2 adds more core data-binding features and better validation support.  These include:

·         Per-binding Validation and BindingValidationError event handler support on controls (allowing you to handle input validation with TwoWay bindings)

·         Support for binding expressions on attached properties

·         Richer binding value conversion support (including value conversion fallback support)

Isolated Storage

Silverlight enables applications to store data locally on a client (via a feature we call "Isolated Storage").  Applications can prompt users to grant them size permissions for this storage (for example: a user might grant an email program 50MB of local storage). 

Beta2 increases the default local storage space provided to Silverlight applications to 1MB in size.  Beta2 also now provides better end-user support for managing per-site storage permissions, as well as the ability to easily revoke/delete an application's local storage.  Management UI to control this can now be brought up by an end-user by right-clicking on a Silverlight application and choosing the "Silverlight Configuration" menu option.

Understanding Compatibility with Silverlight 1.0 and Silverlight 2 Beta 1

Silverlight 2 Beta2 is compatible with applications that target Silverlight 1.0.

Silverlight 2 Beta2 will not run applications that target Silverlight 2 Beta1, since we've made a number of API changes between the two betas for the new features being added in Silverlight 2.  Browsers that have Silverlight 2 Beta1 installed which visit a site that hosts a Silverlight Beta2 application will be prompted to upgrade to the newer beta of Silverlight.  Once they do this they won't be able to run Beta1 applications without uninstalling Beta2.  This means that if you have published a running sample on the web built with Beta1 you will probably want to update it to Beta2 soon. 

We have published a document that details the changes between Beta1 and Beta2 here that can help with this.  I also recommend reading Shawn Wildermuth's What Changed in Silverlight 2 Beta2 and Upgrading your Silverlight 2 Projects to Beta2 posts for more details on some of the changes between Beta1 and Beta2.