When the Google was set up on a project which was to win over the language barriers, I thought it was some kind of project that is equal to building the great pyramid of Giza again.
This service helps users to translate a part of web page or some text to another language. This service, in other times, would have required a professional person; and you would have probably needed to pay for it. But Google offers it for free.
But Google translation is just like other automatic translations tools, after all, and has its own limitations. You can use it for translating only general content of your text or webpage. There are no grammatical rules.
So in all, Google has lot more to do for its translation tool. But the main question here is how can Google benefit from this service? Benefit mainly includes the production of content here.