Like Stefan, I'm no expert on it, but I'm familiar with a few concepts.
First off, division by zero is defined as "undefined" by mathematicians, but if you take the calculus concept of the limit and take the denominator from some non-zero value closer and closer to zero, you move the fraction's value toward infinity.
The notion that division by zero is "undefined" is curious, though. I certainly like thinking of 1/0 as infinity. But then, if we follow the "rules" of mathematics strictly, then we run into a curious paradox. For instance, n/n = 1 (usually), but what happens if n=0? Then, 0/0 should be "1," but zero in the numerator usually makes the value equal to zero. And then zero in the denominator approaches (arrives at?) infinity. So, 0/0 has three values or none of them -- 0, 1, infinity. And perhaps this gives us an interesting peek at a relationship that may underlie all of reality.