In my own case, Ropbert, since my programming time is lesseened at this wire manufacturing company by whom I am employed, I have taken a couple C# classes; I've seen 2002, 2003 and 2005 versions of .NET; there has been quite a bit of huge growth between these versions, and none of them are backward compatible. You cannot use 2002 on a 2005 version of VS.NET at all. It has to be converted, if it can be. At least FoxPro has been truly backward compatible in most cases.
I do want to learn C# somewhat, but I am not sure at the grand old age of 53 that I want to get all worked up over it. I may go to law school instead. Or, maybe the world wil end as we now know it, or maybe the economy will crash. Okay, now that's getting a bit dramatic.
Actually, I would like to learn more about Visual FoxPro's capabilities and even do some SQL and Web stuff. That gives me enthusiasm, but when I think about Visual Studio.NET, I think "P-A-I-N". It is because the core of this product seems to change so dramatically and there will surely be a major requirement in time and effort to study this new product (.NET).
Okay, I've rambled enough here.