This Google Siri-like service in the latest Android update simply looks like it will put Siri to shame. Take a look at the video below.
As you can see from the video, the voice-search function allows the user's request to be transcribed, something that Siri is unable or doesn't want to do (Apple does try to give Siri a personality), and bring the results back up faster.
Obviously, this demo Google put forth was under a controlled environment and I'm sure real world use mileage will vary. Still, it's fantastic to see Google get into this. However, that is not to say that Apple, Microsoft, or even Nuance are not trying to innovate further here.
Competition is great and mobile search isn't like desktop search so Google has to still find its footing in all this. A large portion of its revenue comes from traditional browser search and Google has yet to find a way to monetize mobile in a big way.
Maybe this is the first step. I know this much. Apple and Google definitely are going about this in different directions.