One of the coolest parts about Google's I/O keynote was the Voice Search introduced in Jelly Bean to compete with Apple's Siri. That was a staged demo though. Google could have mucked with the presentation to make it seem better than it actually was. How about a live demo from a person who got a Galaxy Nexus at I/O?
Jean-Louis Nguyen went to Google I/O and he got his hands on all of the goodies that Google gave to developers. He wanted to put Google Voice Search to the test and posed 47 actions (questions, directions, etc) to the software. Its performance was on par with, and sometimes exceeds, what you get with Siri. It's a rather impressive real-time look at what Google Voice Search is capable of.
Check it out:
As you can see, Google Voice Search coupled with Knowledge Graph is a powerful combination indeed. Siri can perform these same actions with help from Wolfram-Alpha, but I still got to give the edge to Google. That doesn't mean that Apple is forever lost as I'm sure they're coming up with more ways to improve Siri, or they'll just sue Google to avoid having to innovate on Siri.
Nguyen does say that there are some things to keep in mind when dealing with Google Voice Search. It seems that it requires users to say specific things when asking certain questions. It just means that Voice Search is not all knowing yet so we have some time before it begins to indoctrinate humanity.
1. Google will give you walking or driving directions directly, if you specify it. Asking for transit or biking directions does not work at the moment.
2. Google is able to distinguish how 'long' a bridge is in length vs. how 'long' a movie is in duration. That's assuming the data already exists in the KG.
3. Local search, coupled with auto-correct, is able to properly locate and spell 'Worcester Mass' and 'Wooster College', even though these places are in different states and can be pronounced the same way (or at least, I did).
4. The voice will speak back any answer it finds in the KG; however, Google currently requires that your query somewhat matches the way attributes are labeled in the Graph. For example, asking for the 'height requirement' of Space Mountain works, but asking 'how tall do I have to be for Space Mountain' does not work at the moment, because this particular data is labeled as 'height requirement'.
5. In order for answer cards to work properly, everything on your device (and the Google Now app) must be set to US English. More languages will be available soon.
I do want to make one special mention about the end of the video. It shows that Google hasn't forgotten its past with fun easter eggs and referencing memes. I won't ruin it, but it brought some joy to my day to see Google including a tired, old meme among the many things that Voice Search is capable of.