Google's new platform, Instant Search, displays and predicts a search engine results page (SERP) while the user is still typing. Like the auto-complete feature, this instant search pushes the user into a well-traveled road hoping to make the search faster and more streamlined.
Unfortunately for the advertiser, the well-traveled road means less opportunity in the long tail. With more advertisers competing in the same space, the auction prices for head terms will rise in both volume and price, at the expense of less expensive/less common search terms.
A worst-case scenario, and perhaps overly dramatic, is that tools like AdWords shift in nature from high ROI opportunities to brand awareness focused, and thus perhaps reducing the sheer volume of competitors in markets. But Google is significantly less concerned with smaller markets.
This push appears to be aimed at reducing search creativity, especially in verticals such as law, education, real estate, and wealth management. This will make the challenge for smaller advertisers looking to take a slice of major competitors' market shares all the more challenging.
While the move will certainly have an adverse impact on advertisers, the impact will be mitigated by the fact that instant searches really only work through Google.com. A significant percentage of search queries still take place within browser-specific toolbars, with which Instant Search isn't available (yet, at least).
The shift to instant search will also likely have a significant impact on CTR data for advertisers. The impressions data in AdWords accounts will likely spike because, according to Google, an impression will be counted if a user stops typing for three seconds.
In terms of search engine optimization, there really appears to have been no algorithmic shift that accompanied yesterday's change. The focus appears to have been more geared toward display of search results than the weighting and authority of the results. Like paid search, the swing will push the number of organic queries toward head terms, which will likely favor sites that have higher authority and are more thematically related to the broader term.
From the searcher's perspective, the move appears to be mostly positive, but Instant Search now marks a significant shift in search as Google is now taking a much more active role in not only leading searchers to not just the answer, but also the question itself.