Damn, this is frustrating, i just wrote a huge reply and then my internet connection bunked out on me, and i couldn't get back to it.
Ah well. Well, this is a really good question, and opens up a lot of angles to talk about. To begin i'll answer the immediate question, Do i believe in Destiny?
Yes and NO.
Yes, i believe there are certain paths that one should follow to suit their temperament and personality, but these paths are not carved in stone or pre-determined. Instead, they need to be recognized by us, so that they can be followed. So in essence, yes i believe there are "right paths" or "proper paths" for us to follow, but they are not entirely chosen for us already.
Onto free will and choice. When i said there are "proper paths" that suit us to walk down to fit our temperament and personality, i didn't mean that we only have these paths to go down. We have tons of them, but these "paths" are the ones which realize the potential that we are as an individual, and therefore is the "right path". So these "right paths" are in effect, our destined path, that would best suit us, but they haven't been chosen for us. Instead, we have to recognize them, so what we consider free will and choice come into play, but it really isn't entirely free, in that we already know what choice we should make, and only need to recognize it. So while we are choosing what to do, in effect we are really trying to "find" the answer, instead of the idea that we are making it entirely on our own. So I think free will is balanced by our nature towards something, and a "choice" is made when we try to fit a situation that best suits our nature. I hope this isn't too confusing.
Destiny then, is the fulfillment of our nature, that we can either meet, or not.
As far as psychics go, i don't believe they have any special view of the future. I think that what they do is propose a "future potential" or a probability of what could happen depending on the variables existent in an individual's life and their nature. So, while it may seem they have a bird's eye view of what lies ahead, i think mainly they have a heightened intuition from which they can sense what an individual is all about and predict what will happen to that individual based on their circumstance and nature. From your name, your employment, where you live, the inflection of your voice, the clothes you wear, the words you use, they can extrapolate from this to give them an idea of where you are coming from. Its almost statistical in a way, because from these things they can get a fair idea of your socio-economics and what is included in your situation, and then can go from there.
So I don't think their decisions are made out of a vacuum of some "great insight" i think its a combination of intuition, reasoning, and probability. So, in many ways, i think many psychics have almost a scientific understanding of things, that they pull from, and not the mist of a crystal ball.
And that's pretty much it.