1) the left-hand column is counted as non-search, when the left-hand column is entirely about search. The left-hand column gives you ways to refine your search: you can limit the types of search results like news/images, slice/dice search results by date, limit search results to verbatim matches or to change the geographic weighting of search results, etc.
2) the actual search box is counted as non-search, as are the estimated results count and the time the search took.
3) the article treated whitespace as non-search, when shorter columns can actually make it easier and faster for users to scan the results.
That's still leaving aside facts like
- We actually think our ads can be as helpful as the search results in some cases. And no, that's not a new attitude. I found a quote from 2004 that said "In entering the advertising market, Google tested our belief that highly relevant advertising can be as useful as search results or other forms of content," and I'm sure I could find similar quotes with a bit more looking.
- And of course there are tons of searches where we don't show ads. A lot of people like to take a query that shows ads and say "Aha!" but they're forgetting all the queries that don't show ads.
Not to mention that our ads aren't just a straight auction; we try to take into account things like the quality of the destination page in deciding whether and where to show ads, just like we do with web search results.