You know Telerik's commitment to provide cross platform Silverlight and WPF controls with shared code base.
Now that you have all those cross platform controls (more to come in Q1) - what is the next step you need to do in order to have your application working in SL/WPF with a shared codebase? This is an easy question - you need to use the guidance provided from the Patterns and Practices team at Microsoft of course :). There is now official documentation on msdn available.
Here is an extract from the project description from the codeplex site:
"The Composite Application Guidance for WPF and Silverlight is designed to help you more easily build enterprise-level Windows Presentation Foundation (WPF) and Silverlight client applications. This guidance will help you design and build flexible composite WPF and Silverlight client applications – applications that use loosely coupled, independently evolvable pieces that work together within the overall application."
The guidance was first created for WPF. From about a year this project is being ported to Silverlight2 too. There are many resources out there about how to use the guidance, but my hint for you is to just grab the code, check the documentation and to play with the samples that comes with the installation.
Pretty cool stuff - save yourself a huge amount of time wondering how to create cross platform applications and go download the bits now!
Valentin Stoychev (@ValioStoychev) for long has been part of Telerik and worked on almost every UI suite that came out of Telerik. Valio now works as a Product Manager and strives to make every customer a successful customer.