It is not really a Google version of Siri. It's more of a predictive contextual assistant with voice recognition. It will literally tell you what you want to know before you ask. For example, if you have something scheduled in your calendar and are leaving your office, it might pull up directions and traffic conditions without any input from you. Or if you are visiting another city on vacation, it might offer up nearby tourist attractions and bus schedules. Google is putting a lot of resources into Google Now, and I expect it to be something that we see more strongly emphasized in the coming months and years. Siri is more limited in purpose than Google Now, although there are some areas where it is more tightly integrated with hardware than Google Now is, which might be expected. I'm not saying Google Now is better than Siri, or vice versa. They serve different purposes, albeit with some overlap.