Ahhh, statistics. The savior and downfall of mankind. It was once said (Mark Twain ?) that there are 3 kinds of liars: liars, damn liars and statisticians.
Part of the reason for this is that although statistics uses mathematical methods to solve (well posed) problems, it is not part of mathematics. Just because you force a set of data through a particular algorithm, doesn't mean that any of the results that come out are necessarily meaningful.
To me, statistics is often a sort of philosophical thing. One needs to think philosophically about what sort of data you have, what kind of data you can get, what (mathematical) tools you have available and what kind of questions you want to ask of the data. The reason for thinking about what kind of data you can get, is that quite often the only thing the original data will tell you is that you need more data. Or different data.
Another problem is that statistics can't give absolute answers to all questions. You can say with certainty, that the average of some sample is X. But you can only guess at the average of a population mu.
Okay, so what lies ahead?