Quote from the article: "In fact, Google stressed that the only information that flows back at all from Chrome is what people are searching for from within the browser, if they are using Google as their search engine."
I'm pretty positive that's not true. If you run Fiddler when browsing with Chrome you will see constant hits to toolbarqueries.clients.google.com whether you're using Google or not. I could be browsing some MS site and toolbarqueries.clients.google.com gets hit. Chromium doesn't do this.
Edit: You can uncheck everything under privacy and it will still send those requests.
Edit2: What it sends back looks something like this:
Looks like auto-fill data, but this happens when I click around a site, NOT when searching Google or typing something in the address bar. For some sites (interestingly, not all) it sends 3 requests for each page load.
That's troubling. I'd be very interested in seeing a response from Google about this. Are you aware of any? Also, can you use Fiddler to inspect the content of the requests? I'm not familiar with the tool.
I see this too, if I have autofill enabled, and at least one autofill address entry.
I would guess that Chrome is sending a hash of the <form> (perhaps URL + method?), plus a hash of each of the <input> tags, and Google returns some sort of information about what kind of form it is?
If so, it would mean it's pretty easy for Google to determine which sites you're on from the pattern of hashes sent for each site. e.g. I see this data sent in the clear for pretty much every page on https://www.facebook.com/
Again, if you actually read the article, you will come across the section titled "What About The Google Toolbar & Chrome?" I encourage you to read it.
[edit] Also, see this comment and patio11's subcomment further down the page, both of which were written an hour before yours: http://news.ycombinator.com/item?id=2165469#score_2165578.