There's been a lot of discussion among the .NET folks recently about the magnitude of the changes that are being introduced in the Windows Workflow Foundation (WF) in .NET 4.0. See, for example, "Windows Workflow Changes Direction" by Kathleen Dollard. It's just another anecdote that backs up the old saying about Microsoft technologies, best stated by Karl E. Peterson:

"Conventional wisdom has it that version 1 of any Microsoft product or idea is really an alpha, that version 2 is the beta, and that the safe money rides on version 3. Then, following version 3, Microsoft generally proceeds to do its best to upset the success it found in that golden release."

Some people have expressed some concern about this significant a change in a "4.0" product, but I think they fail to realize that while the .NET Framework may be at a fourth version, WF was only introduced with .NET 3.0, so it's only on its second version with .NET 4.0.

You see the same pattern with how Microsoft supports web services within the .NET Framework. There has been such functionality included as part of the framework since the initial release, and a separate add-on called the Web Security Enhancements that went through its own initial, 2.0, and 3.0 releases. That all changed with .NET 3.0, when the Windows Communication Foundation (WCF) was introduced, and word is that it will also be undergoing significant change with .NET 4.0, though not nearly as profound as the changes for WF (see here).

Database access technology is another area where you see this. Do you remember the time when some of the .NET folks were raving about how LINQ to SQL was the greatest thing since sliced bread? Well, it's another technology on the Microsoft scrap heap now as they focus on Enterprise Framework. You might say the same for how desktop applications render on the workstation. Since the initial release of the .NET Framework we've had WinForm, but as of .NET 3.0 that's beginning to give way in favor of Windows Presentation Foundation (WPF). I can only expect at some point for WebForms to also be replaced with something perhaps based on XAML as well. Since both desktop clients and RIA clients (Silverlight) are both based on it, at some point it only makes sense to make it the standard for rendering applications across all deployment targets.

I don't bring this up to point fingers at Microsoft though. I'm more concerned about what it means to us as PowerBuilder developers. Sybase is hard at work on PowerBuilder 12, in order to make it the version of PowerBuilder that provides complete support for .NET. A large part of that effort has support for WPF and, to a lesser degree, WCF. The question is, what version of the various technologies within .NET does Sybase specifically target? Since there are significant changes to WCF in .NET 4.0, will the version of WCF that Sybase supports be the version from .NET 3.x or 4.x? What if WPF goes through a similar set of revolutionary changes as WF?

What will they do with later versions of PowerBuilder as Microsoft continues to evolve the underlying .NET technology? Will we be facing the same abrupt changes as we upgrade to later versions of PowerBuilder that are based on the newer implementations? Will some of the functionality be frozen with support for the older implementation? Or will Sybase manage to wrap the underlying technology in such a way that we are largely protected from the changes?

All good questions, all of which I don't have answers for. Hopefully we'll hear from Sybase soon as they get closer to the release of 12.0.