Google's Caffeine hasn't even been in a developer sandbox for a month, but the next-generation search infrastructure has already got some search engine marketers thinking about how it will affect keyword alchemy.

Caffeine will substantially shake up search rankings with a larger search index, a longer long tail and more social media listings, according to a comparison of Caffeine versus the current Google search conducted by search engine optimization (SEO) experts for digital marketing agency 360i. 360i SEO Director Mike Dobbs and SEO Analyst Martha Mukangara evaluated rankings in both search engines for 40 retail keywords.

The analysts used 10 major retail brand names as keywords, 10 retail head terms as single keywords, 10 retail "torso terms," or two-word phrases and 10 retail "long-tail" phrases, or four-word phrases, comparing the search results on the first three pages of both engines.

Readers can see the charts the analysts created on Google Watch here and see Google search engineer Matt Cutts discuss Caffeine here.

First page rankings shift about 15 percent in Caffeine, while one and two-word phrases saw up to a 50 percent difference in the domains appearing within results 1 through 10, Dobbs and Mukangara wrote Aug. 24 after testing Caffeine against the current Google search infrastructure.

The research indicated that the search index of single keyword search relevance will increase, meaning SEMs' Websites will compete against a larger pool of Web catalog pages indexed for single word brand or head terms. The reason for this: Caffeine will index more Web pages, boosting the potential results pool and making it more competitive for those trying to get to the top of the page. "This adds value for searchers because it will ideally increase the accuracy of results," the analysts claimed.

While there are more pages indexed for single word brand and head terms, Caffeine's index for multikeyword phrase searches appears smaller, meaning SEMs' pages would likely compete against a smaller pool of pages for more accurate searches. The analysts believe this could give larger brands an advantage for their product and deep level pages, which could boost in relevance for long-tail searches.

There's been a social media explosion since Google's last major Big Daddy search guts upgrade from 2006, and that is reflected in Caffeine's results. Thanks in part to a boost in YouTube's popularity, there are more social media listings compared to Google Decaf. Caffeine is indexing less blogs, review sites and wikis and more multimedia-sharing sites, such as YouTube and Facebook.

Also, with Google increasing its focus on universal search -- adding results for blogs, videos, books and other categories that extend beyond the 10 blue links -- Caffeine shows the number of "universal listings" to increase within the first three results pages.

Finally, the experts said Caffeine generates search engine results pages (SERPs) in half the time. Improving usability and the user experience of Google through speed is a major concern of Google co-founders Larry Page and Sergey Brin, who crack the whip on Google engineers to make the search engine faster.

The analysts concluded that Google through Caffeine is trying to improve the search experience with faster, more relevant results "from a wider swath of the Web's content. This is good news for everyone – Google, consumers and marketers."

To wit, the analysts cautioned SEMs to keep a close eye on their own set of keywords and determine how results change should Google flip the switch to Caffeine.

"Since this is not an algorithm update, altering your best practices or natural search tactics drastically is not recommended," the analysts wrote. "However, if your keywords shift in rank, you will need to refresh your strategy and focus in on any results drop-offs, or take advantage of subsequent wins."