What are some quick patterns for good architecture in WPF?

I was once saved considerable pain by being advised to use DTO's in WinForms by a fellow stackoverflow member. Currently I'm on a WPF project where I would like to make at least most of the best choices, be they standard object-oriented principles or WPF-specific. We already use MVVM. What 开发者_Go百科are the obvious, and maybe not so obvious, things I should consider to reduce the amount of coding and ensure maintainability?

Use RelayCommands instead of RoutedCommands. You can look at this article for more information about them: http://msdn.microsoft.com/en-us/magazine/dd419663.aspx#id0090030.