Is "Search" Advertising?

When I think of advertising on the web, I think of three different flavors:

1. Search: Listings on Google or some other search engine.
2. Display: Banners or other types of static or moving ad units.
3. Social media: Advertising disguised as something else (blog, website, online community, etc.)

The most effective seems to be "search." It accounts for over 40% of all on-line ad dollars. From what I've been told by web experts, it seems to provide the best ROI in most cases. (Having said that, let me assure you that all data in this area is somewhere between "best guess" and bullshit.)

The question I have is this: Is search really advertising?

In the broad sense, all paid messages done for commercial purposes can be considered advertising. However, advertising as we know it in the common vernacular has certain characteristics:

• It is purposefully created.
• It tries to improve our opinion of the advertiser.

If you accept these characteristics of advertising, it is hard to determine whether search can be defined as advertising.

• Search results are sometimes created purposefully (e.g., meta-tags for paid search), but mostly they are "generated" not created.
  
• Its power to improve our opinion is downstream i.e., it relies on the strength of the actual ad (landing page, website, etc.) that we don't see until after we leave (click out of) the search engine.
  

The best analogy we have for search in the offline world is the Yellow Pages. In the Yellow Pages, we distinguish between a "listing" and an "ad."

As a matter of fact, Yellow Pages listings often conclude with the following type of statement 'see our ad on page 345', acknowledging the difference between a listing and an ad. In search, however, we often make no such distinction, and consider the listing itself to be advertising. It may be advertising in the broad sense, but is it an ad?

Your opinion please.

Coming Soon: The Crisis of Advertising, Part 4 - The Brain Drain