Windows Presentation Foundation (WPF) offers Windows developers a new style of development.

Instead of firing up Visual Studio and putting together a standard Windows Forms UI, you can split the development between a designer (or team of designers) using Expression Blend and a programmer (or team of programmers) using Visual Studio.

The design team can use a tool that is familiar to them to design the UI and the programming team can use a tool that is familiar to them. Their common currency is XAML. XAML (Extensible Application Markup Language) is an XML file that describes how the screen should look.

Here's a screenshot from Expression Blend:

Wow. That sure isn't Visual Studio.

Timelines? Storyboards? Animations? Oh, my!

So should I use WPF or not?

Here's my decision process:

1) Is this a consumer app or an internal business app?

In other words, will people pick my app because it looks good or will they use it no matter how it looks because it can help them make money (or they are mandated to use it by the people who hope to make money)?

If I begin a consumer oriented app that will live on the desktop, I will pick WPF and Expression Blend without a doubt. You simply cannot make a Windows Forms app looks as good as you can a WPF app.

If I am making an app that ISN'T a consumer app, then I have to ask another question.

2) Do I want to use tried and true Windows Forms or prepare for the future with WPF?

So I'm working on an internal app that will be used by people within my company whether they like it or not. Should it be WPF? That is a tough question. It is possible to make an app with WPF that looks remarkably like a Windows Forms app. Problem is that many of the standard controls available to a Windows Forms app are not available to WPF.

The not so simple answer is that if I use WPF it will be possible to redo the UI at a later date with lots of spiffy new shiny pieces, BUT it will take me longer to produce than a Windows Forms app. If I use Windows Forms, I will finish sooner, but when I'm done, I'm done. To move to WPF at that point will require re-writing the app.

For Brains-On-A-Stick (my podcast agregating app), I'm using WPF and initially creating a very pedestrian UI. Once all the plumbing works, I'll re-do the UI in a variety of ways using WPF and XAML.

If you want to see a WPF podcast player check out Podder. I haven't looked at it much since my app is fairly similar and I don't want to be influenced by their app. The screenshots look great. They took an approach similar to mine by creating a very basic looking app then handing it over to a designer. They are even having a skinning contest.

The big difference in their app and mine is that they are a player whereas I'm more concerned with maintaining libraries and synching them with multiple devices.

Once I get the first whack at mine complete, I plan to look closely at theirs and see how they implemented skinning, etc.