One of the main issues for advertisers (as far as I can tell) is that this increases competition for the keywords which Google predicts first, and decreases traffic for the other keywords.<p>This already happened with Google Suggest, but I think that Instant search will result in even more users only interacting with the first suggestion.<p>For example, the term "social networking" will now get far more traffic than "social network", because it appears first.
If I wanted to search for "social network", I can't just type it, I have to type it, press down, then press enter. Otherwise, I'm still searching for "social networking".<p>It creates more of a winner-takes-all market in search terms.