Hitwise released a report yesterday showing that Google has posted a year-over-year increase of 8% in its share of U.S.-based search queries, for a total of 72.11% of all U.S. searches conducted over a four-week period that ended Feb. 28. Yahoo, Search, MSN Search and Ask.com received 17.04 %, 5.56 % and 3.74 %, respectively, and are down year-over-year at -17 %, -20%, and -10 % respectively. Here is the total search engine share breakout, as provided by Hitwise:

So not surprisingly, Google continues to dominate and increase share, while Yahoo, MSN, and Ask are tanking, which is also not so surprising for Yahoo and Ask since they threw in the towel a long time ago. Two years ago, Yahoo president Susan Decker proclaimed that being tops in search just wasn't their thing any more;and Ask lost all momentum last year when they said they were ditching the universal approach to become a targeted demographic search engine for women. MSN is at least trying, so there is some hope they could increase their share to 10 % or more in the next few years, most likely through an acquisition of the Yahoo! search property. As long as Google doesn't violate users' trust and also avoids a major privacy snafu, expect to see their share continue to increase, taking bigger chomps out of the remaining top tier providers.

I'll go out on a limb here and predict that Google's share goes to 85 % or more in the next 18 months. The reason? Very simply, they have better search experience, better search services, better ideas on the backburner, better reach, and no formidable competition. Many of the clients I work with already receive 80 % or more of their traffic from Google, though there are some anomalies where MSN and Yahoo! are besting the averages above.

So perhaps one of the other Google killers may be the candidate to take a chunk of Google's share? Don't hold your breath. Any new play in the search space that comes in calling itself a "Google killer" is doomed to failure. A real killer will come unannounced, and most likely not come in the form of a traditional search engine (though this killer won't be Facebook or Twitter, despite the hype -- those comparisons are apples to oranges).

With this news of increased share for the Big G, here is the obvious implication for search marketers that should not really be news at all: When starting a major paid or natural search campaign, your engine of choice should start with Google. That is of course, unless your search plan requires an audience demographic that skews toward Britney.

Longer queries are becoming more common

Hitwise also noted that longer queries - averaging at five to eight words in length - increased by 0% between February 2008 and February 2009. Searches with more than eight words increased by 20 %, while shorter queries of four words or less have decreased by 2%. The majority of searches utilized two words, totaling 23.47 % of all queries.

The other implication from this data is that, if you aren't already doing so, keep digging deeper into your research and planning efforts, and include those wider, more specific queries. This data follows a consistent trend that searchers continue to become more sophisticated with their queries, and that their expectations for finding what they are looking for are being met.