The only thing harder than developing the software is maintaining the software, especially when you need to go through any kind of upgrade/change process, be it the library you use, the IDE and/or the framework or simply an algorithm change in a single source code file. Thus if a code base you rely on is about to change, you generally want to avoid using it until the situation stabilizes.

On the other hand, by the time things are stable and working fine, your competitor has already built and shipped not one, but two versions of their product and you are late to the market, so you have to use early code in the shape of Community Technology Previews, Betas and Release Candidates. That beta 2 will break code you wrote for beta 1 is practically given, but that's the price you pay - code evolves over time and there are no guarantees during beta period. However...

Look at the following screenshot of Visual Studio 2005 beta 2 Output window (I tried compiling one of the examples built using beta 1):

In two cases, I was given exact instructions - a class has been renamed. On another I was given link to the Web page that describes what to do. On yet another the IDE took a "guess" about what I am trying to do and offered one possible alternative.

Now that's what I call attention to details and encouragement for developers to try the bits early. This way you are not afraid of investing time and effort as early as possible because you now that Microsoft will make sure that your upgrade path is as painless as possible. Developers that made this happen, I salute you.