From the Expression Blend blog; An Introduction to Behaviors, Triggers, and Actions Behaviors Under the Hood – API Details and Constraining the Type My only worry about some of this stuff is that it seems to be happening in Expression Blend rather than in Silverlight itself and that makes me wonder; What happens for the Silverlight developer who’s not running Blend? Will this functionality ultimately end up duplicated back in Silverlight itself? How does this line up with what’s already in WP

From the Expression Blend blog;

1. An Introduction to Behaviors, Triggers, and Actions
2. Behaviors Under the Hood – API Details and Constraining the Type

My only worry about some of this stuff is that it seems to be happening in Expression Blend rather than in Silverlight itself and that makes me wonder;

1. What happens for the Silverlight developer who’s not running Blend?
2. Will this functionality ultimately end up duplicated back in Silverlight itself?
3. How does this line up with what’s already in WPF and what does it mean for code/XAML that needs to move between both? WPF already has Triggers and Actions so how does this line up?

From what I’ve seen though, the functionality offered by Behaviours and the way that the designer surfaces it is very impressive so I’d expect them to become pretty pervasive pretty quickly.