In my opinion, being able to track how people are finding your website through search engines is one of the most important data points available to business owners and marketers.

After all, since SEO can make or break a website, knowing which search terms are producing organic traffic is crucial to evaluating your SEO success and analyzing what you can do better.

But a new change that Google is testing makes it impossible to track this data if you use a third-party analytics provider.

That’s according to analytics provider Clicky, which started noticing a significant number of search referrals from http://www.google.com/ with no query string data indicating which search term generated the request.

Thinking that something was wrong, Clicky investigated further and learned that Google is testing the use of AJAX on search results pages. With the AJAX in use, Google’s search results look like http://www.google.com/#q=term as opposed to the usual http://www.google.com/search?q=term.

The problem with this is that browsers don’t include any characters after ‘#‘ when they set the referrer. Because of this, analytics providers cannot tell what the search term used was when Google uses AJAX.

Needless to say, given how dominant Google is in the search market, this is very problematic. And if implemented across the board, it could threaten the existence of third-party analytics providers whose services will lose a significant amount of value if their clients can’t track which search terms are driving their Google traffic.

So what gives?

At this stage of the game, it’s anybody’s guess. Google’s response to the concerns that have been echoing throughout the blogosphere: it’s only a test guys.

Some, however, are suggesting that Google could use this change (if implemented fully) to make its own analytics service more compelling. After all, if Google wants to, it could almost certainly update Google Analytics to ensure that Analytics users still have access to the valuable referrer data that third-party analytics providers can no longer offer.

While I’m not prepared to jump to such conclusions, it does seem odd that Google would be testing AJAX search publicly if it wasn’t giving serious thought to rolling it out on a larger basis. The fact that quite a few people noticed this based on the data they saw in their analytics packages demonstrates that this was not just a small, negligible test.

It also seems odd that Google would not have immediately realized the implications this would have for third-party analytics providers and their users; assuming, of course, that it even cares about them.

This is definitely a story to watch and regardless of the outcome, it should serve as a reminder of just how enthroned Google has become. With the flip of a switch, Google has the power to create virtual nightmares and threaten the existence of other businesses.

At the same time, by flipping the right switches and leaving some where they currently are, it can do the right thing. Hopefully in this case it will remember that little ‘do no evil‘ pledge.