> You could have given the same feedback in a way that is much less likely to come off badly by simply saying "I've really a UNIX kind of guy and a Windows shop probably isn't the best fit for me."

This also has a good chance of being interpreted badly. Depending on who reads it, picking Windows for your development environment could make sense. Lots of Java development is done on Windows and Windows laptops are a very common sight on Java-related conferences.