If you haven't played with either WPF or Silverlight, you first need to understand the tooling we have available: Visual Studio, Blend, and Design. Most people don't consider Expression Design, but I'd argue that it's perhaps the best way to get started, depending on what you're doing. This is probably common sense, but if you haven't played with each of the tools, you may not realize how valuable each is to your end goal.
Any developer will most likely want to start with Visual Studio. Try it. You'll find yourself wondering where to start. If you're an old school web developer, like me, you'll stare at the XML code and wonder what to type and finally fall back on the toolbox. If you're a drag-and-drop type (either Win or Web Forms), you'll probably go directly to the toolbox. In either case, you'll most likely find it useful to tweak both the designer and XML... well, that's not completely true. If you're comfortable with XML, you'll eventually stop using the designer because it's just too much of a pain to deal with in Visual Studio. Visual Studio is the best environment [today] if you want to modify markup or code. Don't choose Visual Studio if you're a drag-and-drop type of developer. No matter what type of developer you are, however, you'll find yourself wondering if there's a better way because it just doesn't "feel" right. This is when you'll begin to wonder about that "Blend" thing you heard about.
If you're proficient in Flash development or claim the "designer" moniker, you'll probably start with Expression Blend. Blend is the best tool to build an interface along with some key interaction details (read: animations). The problem with blend is, there's absolutely no intellisense in XAML, which I find ridiculous. And, just to put salt in the wound, you can't even edit code (C# and VB) files with the tool. This really drives in the fact that the tool is intended for no-code applications. These don't exist. In my experience, Blend will become less and less useful over time. Why? Because you'll start to realize you can't do everything in XAML and will have to move some things to code. This, in conjunction to run-time bindings in XAML will render the Blend design-time experience useless. Visual Studio is the same in this aspect, but it just because apparent that you'll prefer the intellisense, since you'll want to work with the XAML. Unlike Visual Studio, tho, you'll find yourself tweaking the designer more than the XAML. Coding isn't the only thing that will take you out of Blend, tho.
Let's face it, most people start looking at WPF and Silverlight because they want glam. They want beautiful applications with all kinds of frou-frou animations and transitions. This drives me crazy, but I'm not surprised. Choose WPF and/or Silverlight not because it can be pretty, but because it's the next generation user interface technology. This means, if you're building a new Windows application, don't even look at Win Forms. WPF is the way to go. Microsoft hasn't said it, but Win Forms is dead to me. If you have an existing app, I'd recommend you start looking into interop scenarios. Whether you're looking at WPF and/or Silverlight as the next gen platform or not, you're still going to want that glam I mentioned. This is when you should take a look at the often ignored, red-headed step-child of the Expression suite.
Today, Expression Design is a vector graphics editor. Don't expect to switch to Design for raster images (i.e. GIF, JPG, PNG) -- which is what I was hoping to do -- you'll find yourself missing crucial capabilities. I keep Paint.NET on hand for these needs. Design is best used to build creative visual interfaces. I've used it to theorize and bring certain design elements to life. You might do this with windows, buttons, and other framing elements, for instance. I simply find Design to be a better interface for adding glam to my user interface. Note that I'm not referring to animations. Use Blend for animation; use Design for static visual elements, like rotation, embossing, and the like.
To sum it all up, here's what I believe a WPF/Silverlight project should looked like.
- Know the difference between graphic and interaction design. Essentially this is the user interface vs. user experience debate, it's important to know the difference for staffing purposes. There is a difference and it's substantial. Don't assume that a graphic designer can architect an ideal interaction or vice-versa.
- Get a graphic designer. Unless you have an eye for graphic design, you won't be getting the eye candy you're probably looking for. If you have a passion for this, but it isn't your calling (like me), you might be able to get there eventually, but your time is probably better spent elsewhere.
- Get an interaction designer. The fact that we have dialog after dialog and click after click proves how important this one is. I'd argue this is more important than a graphic designer, but I might be biased. The good news is, this can be learned a lot easier than the artistic nature of graphic design. Don't think you can get there without dedication, tho. There are some scientific guidelines, but I have yet to see a good roadmap. It's more about opening your mind and removing yourself and what you might do from the process.
- Design is the graphic designer's scratch pad. Whether you start with wire-frames or set your sights on the real deal, Design is great for slapping something together that will eventually be useful. Tweak and tweak and tweak until you get something that looks right. Then, export to XAML.
- Blend brings your design to life. Now that you have your XAML, you'll probably need to tweak it to make it slightly more human-readable and maintainable as well as do some initial bindings and animations. This is where three worlds collide. Graphic designers will feel awkward in Blend, but will still be able to be relatively production; interaction designers don't really have a tool, so it will depend on where they came from, but Blend is arguably the best place for them to get started; and, developers are typically more code-focused, so Blend will be awkward for them, too. The bottom line is, Blend isn't the perfect tool for anyone, but it does fill a need. Use it to add interactivity to your design.
- Visual Studio gets the job done. When you're ready to make your app do something real, open it in Visual Studio. Arguably the worlds best development environment -- although not without its flaws -- you know why you're here. 'Nuff said.
As a developer who is very comfortable with markup, I've found that this has changed for me over time. I still believe it's a great workflow that supports some moderate back-and-forth -- at least, between Visual Studio and Blend -- but my habits have changed over time. As I've become more and more familiar with XAML, I tend to create visual and interactive effects in Design and Blend, respectively, and then just look at the XAML to figure out how it's done. Occasionally, I'll open my app in Blend, but not too often. This just depends on how big of an effect I'm trying to implement.
The bottom line is, get some experience in all three of these tools. You'll find your own comfort zone. It may include the all-too-bloated and usability-hating Photoshop with a XAML exporter instead of Design or augmenting XAML editing with a light-weight tool like XamlPadX or Kaxaml. No matter what you grow into, know there will be growing pains. WPF and Silverlight have a huge learning curve, but you're buying into the future. The curve is there for a reason, but will hopefully be lessened as the tools improve. I'm also hoping for some major improvements in .NET 4, but I'll try to touch on that later.