The series of caveats there tells a tale of it's own. Google Now is so far ahead of Siri, there's simply no comparison... starting with the basic magic of automatic contextual updates and notifications without even asking ("Your flight has been delayed by 30 minutes", "Heavy traffic on 101. Leave in 10 minutes to reach your meeting on time" etc.)
Add to that almost perfect voice recognition with any accents in the world, automatic language recognition etc and all that backed up by Google search engine. Sorry, calling out Siri as a Apple's superior cloud service is simply not credible at this point.