Yeah I was thinking that in terms of voice talk/respond, Siri is way ahead of Google Now. When I played with it, Google Now really doesn't understand a wide range of phrases and defaults into chucking them into a Google search.
However, the non-voice related aspects of Google Now (which is consistent with everyone's praise of Google Now) doesn't have a 1st party equivalent
This is exactly my thinking as well. I've played extensively with Google's Voice Actions, and Google's speech recognition on a Nexus 4, and I've used Siri on an iPhone 5. I thought in general that Google's speech recognition capability is a bit better, but it's actual list of "action" words seemed smaller and more limited, and I had to choose my words more carefully to get it to do what I want it to do. So in terms of speech recognition, I've overally been more impressed with Siri than with Google's speech recognition.
But Google Now is a totally different piece of software and I'm totally in love with that. But that's not really a Siri replacement and has very little to do with speech recognition at all... it's more like a new and different virtual assistant capability that isn't even relevant to a discussion of Google's voice search vs. Siri. People can debate which is more useful for their daily needs - Siri or Google Now - but comparing the two in terms of which is "better" is a bit like comparing oranges to Apples.