John,

The quick answer is ... It depends. You always have to climb a learning curve when learning a new language. I'm sure there are lots of Fox programmers out there who dropped in productivity when they moved from FoxPro 2.x to Visual FoxPro. Sure, the language was similar, but this whole new OOP thing was foreign to many who had to get their heads around that first.

I think something similar can be said for .NET ... not so much learning the OOP thing (we should all know that by now <g>), but learning the .NET Framework. The language itself (be it C# or VB) is no big deal ... is is, after all, only different syntax for the most part. But learning which Framework namespaces have which classes and how to use these classes as a building block to development is the part that takes time. Once you've learned it I don't really think productivity is an issue any more. At least that's the case for me. I'm curious what other responses you'll get.

~~Bonnie