The survey is closed. Here are the results.
What language do you use most to program applications that access USB devices?
These were the options given:
Visual C# .NET 90 33%
Visual C++ 83 31%
Visual Basic .NET 35 13%
And these were write-ins:
C/C++ 26 10%
Visual Basic 6 11 4%
Delphi 9 3%
Python 5 2%
Java 5 2%
Power Basic 2 1%
Assembler 2 1%
PHP 1 .5%
Thanks to everyone who responded. It looks like variants of C/C++ remain popular, followed by Visual C# and Visual Basic .NET.