Ummm... good question. I guess it's a combination, but it's also from my own prejudices, there are places that just attract me, and there are places where I wouldn't go unless someone paid me for that
, for instance, I doubt I'd ever go to Ukraine...
But what really limits my trips is the budget, if I could afford it, I'd go to the most exotic places, but since that's not possible all the time, I have a lot of fun checking cities with Google Earth too...
Others' opinions are also very important as well. And documentaries... magazines don't inspire me at all though.