Great video, but I think there are some more advanced uses of the DataAnnotations that could use some further elaboration, especially in DynamicData websites since it is so templated and annotation driven.
For example, I have a Customers table that has separate columns for first and last names. It has a 1:M relationship with both Orders and Phones. In the default Dynamic Data website, the display field for the foreign key will be the first name column. That's obviously problematic, so what I would like is for the full name to be displayed instead.
At first, I thought I would need to play with the auto-generated templates or create a slew of custom pages. But it it's far easier than that...
In this use-case, all one needs to do is create a partial class for the table in question, add a public property to the class that exposes the desired information, and then use the DisplayColumn annotation (http://msdn.microsoft.com/en-us/library/system.componentmodel.dataannotations.displaycolumnattribute.aspx) to the user-defined property.
Perhaps a series of mini-videos for data annotations are in order, or a reference to other tutorials where one finds more information about them (I imagine in ADO.NET Entity Services they appear a lot, though I haven't seen those yet) would be a good thing to include in subsequent videos!