I attended the terrific “PRC03 Microsoft Silverlight Inside and Out” presented by Jeff Prosise.  The session was packed with a good background on Silverlight development and a bunch of great tips, tricks and samples.  Some of my favorites were:

Dynamic XAP Loading: you can break apart your xap file into pieces to allow for faster load because you aren’t loading all of your assemblise on initial load of your silverlight app.  You have the ability to do the initial load and only call to the secondary xap files when the assemblies are needed.

Automatic Out-of-browser updates: In only a few lines of code you can have your Silverlight OOB app check to see if there are any updates to the app and install them automatically.  A notification can be thrown to alert the user that a new version has been installed and that they need to close and reopen the app to get the new version to run.

Client HTTP Stack: Silverlight has the ability to us the OS stack, rather than just the browser stack to give you information, such as errors.

External URIs:  Using some samples that Jeff has, located on www.wintellect.com, that allow you to implement calling external URIs rather than ones that are only inside of your solution.

Some of the cool new features available in this release of the Silverlight 5 beta:

Style Data Binding: the xaml version of CSS.  Allows you to do dynamic theming easily.

Data Binding Debugging (aka: XAML Debugging): you now get the ability to put break points in your xaml and debug the same way you can with C#.  Right now it only works with binding expressions, but keep your fingers crossed that they will expand on this dramatically as the beta rolls on.  This demo got a much deserved round of applause.

Trusted Applications in Browser:  All of the goodness of trusted applications that was only accessible in the OOB experience is now available IN Browser!

Trusted Application Out-of-browser enhancements: You can now access the file system completely.  Not just the user’s “My Documents” folder, but the ENTIRE file system.  As an Operations guy this scares me a bit, but it is an ever changing world.

RichTextBoxOverflow:  This allows you to have a better text box experience where, in this particular demo, putting a richtextbox and a richtextboxoverflow in a horizonal scenario Jeff was able to increase the space between characters and show how the text flowed seamlessly from one text box into the next.

Some cool things still to come in the Silverlight 5 beta:

WS-Trust support for services
64-bit support for the plugin
COM interop for trusted in-browser applications
P/Invoke for trusted applications
PivotViewer control improvements and distributed in the SDK

I am skipping a ton of cool stuff that Jeff showed us, but visit his blog where you can read about most of this and much, much more at http://www.wintellect.com/CS/blogs/jprosise/.  I didn’t even touch on any of the Windows Phone 7 goodness that he talked about.

This was my first time attending a TechEd PreCon, and I will definitely be back.  Would have been a terrific value at twice the price.  This level of data dump in a single day is rare, I hope to live up to this standard SharePoint Connections Coast to Coast next week when Corne and I give our “SharePoint Collaboration Bootcamp” PreCon!