"Which part of the article gives you the impression that the author doesn't understand that?" The writer does not see any advantages of the integration of the Google search engine in Google+. I'm sadly forced to understand that he fails to get the idea behind it. Searching in shared posts in Google+ is one of the key features that Google+ has over Facebook and other social networks since it will let you simply search for "that interesting site my friend shared with me last month" instead of going through his posts manually.
My second point was cleared up by true_religion, thanks for that.
Google+ is more natural because of it's Circle system. You don't broadcast all your interesting findings to everyone you know, you tell it to the select group of people who might be interested, just like in real-life. Next to that, as said before, you can search the posts and shares in Google+. You can also see your profile in the point of view of others on the web, in your circles. This makes setting up your profile a lot more natural and easy.
I have to admit that "positivism" is indeed the wrong word. I stand corrected and I'll change it.
"No, they wont. This doesn't even make sense. For one, Siri could bypass Google altogether" Then where will Siri get the results? Siri can't pull them out of thin air, they have to come out of a search engine and if Apple values the "magical" experience of it's users then they should use Google. The user is using Siri as a GUI that takes the Google results and speaks them out. But the results need to come from somewhere.
"I'd guess the author is well aware of this. Are you aware that Apple has bough a mapping company and is looking to integrate its own maps in a future iOS release?" I'm aware of the "3D"gimmick (it's nice to have 3D, but I would prefer to look where I'm driving/walking/cycling) that they bought and the mapping company they bought. But I think that is a bad move, since Apple would then be inventing the wheel again, only to disconnect themselves from Google maps. If Apple is willing to pump so much money into collecting data of roads and buildings all over the world, then they would have set up their own carrier. Since the cost of starting your own carrier is peanuts compared to photographing the entire world.
I hope this made things a bit more clear.