I was worried about this too. However, I did some google'ing which put my mind at rest. Essentially, the way I interpret it is:
-.NET 2.0 is very different to the previous version of .NET 1.0. So, it seems to be much more logical to do MCTS (.NET 2.0) than MCAD (.NET 1.0).
-However, whereas .NET 2.0 totally replaced .NET 1.0, .NET 3.0 is not a replacement for .NET 2.0. It's essentially .NET 2.0 with some more functionality.
So, it looks like a large proportion of the new .NET 3.0 consists of the .NET 2.0.
Considering the .NET 3.0 exams haven't been released yet, I don't think any of us have time to hang around waiting for them to be. And you'll also have to wait for resources such as text Books and Transcender exams to be released for the new exams. I would also expect that there will be an upgrade exam to .NET 3.0 for people who have already done the .NET2.0 MCTS.
That's my take on it.
Good luck
