What is Google Instant Search?
In short, the moment you start typing in the Google search bar, you start seeing the results right away (even before you press the 'Enter' or 'Search' button). As you keep type, the search results change based on whatever you have typed so far. Google Instant Search tries to act smart and presents you search results based on your search string, location, previous searches and other parameters beyond our imagination.

Effects on SEO?
Although it is too early to predict all the effects, but so far some things are quite clear.

1. Long Keywords Based Searches will Suffer:
The moment you start typing, and start to see the search results, anyone will obviously be tempted to click on search results without typing the entire string they had initially in mind. In short the "short tailed keyword phrases" will benefit.

2. Search results on #1 position will benefit even further:
Instant Search suggestion strings now take lot of room, roughly the half of top visible screen. Therefore we will only see the top #1 or #2 search results instead of top #4 or #5 (earlier) without the vertical scrolling. So if you have some pages which appear in top 2 positions, you will likely get more traffic for them now. While if you are on position #3 or more, your blog traffic will likely suffer.

I have already seen this on my personal blog. The traffic on the pages which are on #1 or #2 has increased and those which have a lower rank have seen a significant drop in web traffic. The reason is clear, visitors are less likely to scroll down for search results appearing below the top 2 search results. The SEO competition just got even more bitter.

3. Niche sites to benefit most:

Authority sites like Wikipedia will gain most since they already appear on #1 position for most common searches, but for all other little guys like us, the niche sites will likely start playing a bigger role. You must have noticed that the niche searches normally tend to get more weightage for the top few search results. For example, if you search "Dog Food", the top few results appear from websites dedicated to "Dog Food".

We need to add more information to this article over time. Please share your experience by adding comments.

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