Zynga announced today that they would be taking their company public, or that they would be in the near future. What this means is that they will essentially put up shares of the company that can be bought and sold on the stock market for either profit or loss. The company had not been publicly traded before but with their filing of an S-1 form they soon will be.
There is currently no information as to how many shares of Zynga will be available to the public, nor how much the starting price of each share will be. Basically this means that soon you can make your own little microtransactions and possibly even get money back somewhere in the future if you pay attention to the stock market at all.