If you work in both Blend and Visual Studio you will notice that there are significant gaps in functionality between the two. In Blend you get a rich design and animation interface (and it looks way cooler, too) but don’t get some of the much-needed development tools. In Visual Studio, you get productivity-focused tools like intellisense but lose out on easy storyboard manipulation and the like.
Basically, if you do at least a little of design and a little of development, you need to be running both Expression Blend and Visual Studio.
From within Blend there are a number of actions that will result directly in Visual Studio opening (such as drilling into a click event on a button) if you have Visual Studio installed. However, Visual Studio doesn’t reciprocate the favour when you’re looking for something more design-friendly.
To open your project in Blend directly from Visual Studio, you’ll need to hack together an external tool link.
Go to Tools –> External Tools in Visual Studio and add a new entry to the menu contents. You can set your title to whatever you like (I used Send to &Blend). Your Command should be set to the path for the EXE where you have Blend installed. Lastly, set the Arguments property to the following:
…which will tell Visual Studio to pass the current project path and name to Blend as it opens the project.