It looks like Google is trying to lure more people to work for them. The last ideas have been recently presented on their blog. I am not a specialist in finance, but this looks like just a new way of attracting more people to work for them. And although they pay well, relative to other companies in Silicon Valley, this program seems to be a means of improve their attractiveness to potential employees.
It is important for Google to keep their programers. Many of the good ones are lured by the promise of great increases in the price of their stock options. However, as the company matures, this growth may not be sufficient to keep employees from moving to new companies. In fact, this is the fate of most technology companies in the Valley. Example of this happening can be see in other Internet powerhouses, such as eBay and Yahoo.
From their blog:
We work hard to attract and retain the world's best talent in a number of ways, and a part of that is offering competitive compensation packages. We offer standard things such as competitive salary, cash incentives, restricted stock units and stock options. But we also aim to be innovative. So today we're announcing a new compensation program called Transferable Stock Options (TSOs).Link