Okay, it's just a countdown clock until the date (Dec 31, 2010) by which the Census Bureau must return official state and national population counts, which is kind of lame.
I think it would have been much more interesting and informative if it also had functionality to explain to the American people exactly how the system of apportionment works. It does not require that much math to understand how it works (if you know what a square root is, you have everything you need), although it does admittedly require a significant amount of math to understand what makes the system of apportionment "good."
Initially, each state is assigned 1 representative, to ensure that no matter what, every state (but not the residents of Washington D.C.!) gets at least 1 representative in the House of Representatives; additionally, in order to work without getting into division by zero, the method sort of requires this.
After each state has a seat, the rest of the seats are distributed one by one according to which state currently has the highest "priority" to receive an additional seat.
The priority for an additional seat is calculated as follows: Let P be the population of the state, n be the number of seats currently allocated to it. Then the priority is P/(SQRT(n)*SQRT(n+1))