A few weeks ago I downloaded Visual Studio Lightswitch. I'm still getting to know the application and new features that are offered by Microsoft. You can have a full definition of Visual Studio Lightswitch here:
https://community.altiusconsulting.com/blogs/mikevinson/archive/2010/11/09/microsoft-visual-studio-lightswitch-what-is-it.aspx
I do have to say that the development of business applications has been taken to the next step. I think the most interesting aspect of Visual Studio Lightswitch is that we can now develop apps for the cloud. This is really interesting to me as I'm getting into SharePoint development and I just read that Microsoft will have the Office 365 available really soon.
Anyway the Silverlight team has some interesting tutorials about developing data-centered silverlight apps for the web by using Visual Studio LightSwitch. You can find it here:
http://team.silverlight.net/announcement/announcing-visual-studio-lightswitch-beta-2-is-available/
Also, the MSDN LightSwitch has some easy to understand How Do I videos around Visual Studio LightSwitch here:
http://msdn.microsoft.com/en-us/lightswitch/gg604823