If you're a professional in the software industry your input would be very valuable to him as he's preparing his Ph.D thesis.
He's now at about 500 but bumping that to more than 1,000 would allow him to refine the study further by categories like experience, country etc.
So go here.
Actually you will also find the questions to be a bit of an eye opener when you do, and the larger his survey basis is the more useful it'll be for you as well. A classic win-win situation. So go there and help Thomas now ;)