The sun is quickly setting on 2007, but before we toast the New Year, we here on the Yahoo! Search and Buzz teams have traditionally taken a look back at the year's top trends in search. Billions of search queries from millions of users have always provided a fascinating window into the global cultural climate. This year is no different, but to keep things interesting, we decided to take a slightly different approach to looking at search trends in 2007. Instead of doing a top overall searches list, which is often stacked with celebrity meltdown-related searches, our engineers mined the search data to see if they could identify some more interesting trends that might tell us a bit more about how people are using search and more importantly, what it says about society overall in 2007. They identified seven categories that bubbled up to the surface, many of which were unique to this year. Also new for 2007 are two Top 10 lists using different sources of search data, del.icio.us and Yahoo! Kids. For those who might miss the celeb-centric list, don't fret, it's still one of our Top 10s.

Two of the seven trends - the environment and product recalls - were particularly unique to 2007. While the green movement is certainly not new (in fact the first Earth Day was 37 years ago), 2007 marks the urgency of environmental change among the public. And perhaps what's even more interesting is that a number of the search terms on the Top 10 list - such as recycling, freecycle, hybrid cars and solar energy - reveal that searchers are looking for ways to take action and do something to contribute to the cause, whether big or small.

It will come as no surprise that when it comes to product recalls affecting children or pets, consumers don't mess around. Whether it was looking for official government reports from the CPSC, FDA, or AVMA or getting the actual manufacturer's recall list with product names and pictures, the Top 10 recall list reveals that consumers clearly view search as the go to tool for getting actionable information. And, we also noticed that the public really is interested in the details. Searches on topics like wheat gluten and E. coli spiked as these topics were linked to various recalls this year. I'm guessing most people hadn't heard or thought about E. coli since high school biology.

To get a peek at what was on the minds of the influential crowd on the Web, we decided to look into the top 10 del.icio.us searches. Not surprisingly, many of the top search terms, such as design, web 2.0 and Ubuntu, were tech-focused. But searchers also relied on del.icio.us to help them find favorite sites for their personal passions, whether it be gaming, music, travel or photography. What's interesting about del.icio.us as a search engine is the way in which users use it. Often, generic categories are used as queries to bring up the most popular URLs for that term. But then users start to navigate the del.icio.us corpus by clicking on tags that are interesting to them. For example, "mac" was in the top 10. Not surprising given the del.icio.us audience and some of the press Apple's gotten from its new iMacs and Leopard operating system. A search on mac in del.icio.us brings up a wealth of useful sites and tags that can help users find sites focused on osx, shortcuts, tutorials, webdesign, and even rumors.

Looking back, it's clear that search continues to weave its way into our lives. We rely on it for everything from the most personal interests (our family's safety) to the most global of causes (the environment). We turn to search to stay connected to our world, whether it's the latest gadget or game, breaking world news or water cooler gossip. Search is clearly a resource of first resort.

We'll continue to look into the trends in search in 2007, so check back here for the latest. Our friends at Yodel Anecdotal also posted on Top Trends in 2007 today - check out what they have to say.

Graham Mudd, Yahoo! Search