Thanks
About your popup idea, I'm not sure annoyances will make people want to use or support your program because if I used a program with such things, I would think twice before installing it :D
And I don't really want "forced" feedback too ; I think people that will give the most interesting advices are the ones who really enjoy what you did and feel free to contact you to make sure their opinion is heard.
I've already been contacted in this regard and my post was more about changing the general attitude so that discussion between programmers and users becomes a natural thing more than a shy, embarrassed one.