I was one of the first few hundred users and it was entirely .net/C# questions around this. This was mostly due to Jeff Atwood (at the time) visibility in that

I was one of the first few hundred users and it was entirely .net/C# questions around this. This was mostly due to Jeff Atwood (at the time) visibility in that community - so it had a vast headstart, things have changed since then but that is how it started (well both Joel and Jeff were slightly more visible in the MS communities).