Yes, this is happening. But it's important to examine the reasons why this is happening. When we talk to these developers, they tell us they are moving because they -- and their customers -- require modern OS services and stability, services which are not being delivered by the Mac OS.
In fact, these services are not delivered by Windows 98 either, or developers would be moving to Windows 98 before Windows NT, in theory, because of the larger Windows 98 installed base. Windows NT provides developers and customers with a modern operating system platform, even though in many applications it performs less well than Windows 98 or, indeed, the Mac OS.
This landscape is changing with the introduction of the BeOS and, someday, Mac OS X. Now there are multiple platforms which provide these basic modern services, and so the real question becomes on which platform can the digital design work be done faster and better.
At Be, we believe the answer is on an operating system written from the ground up to provide the kinds of features and performance that these applications demand. You can read more about the reasons why in our Media OS white paper.