Google and Yahoo this week announced 2007’s fastest-growing and top search terms, respectively, providing some interesting insight into the Internet’s collective psyche. Unsurprisingly, celebrity terms remained extremely popular, especially evident on Yahoo’s overall list. Yahoo’s 2007 list of top trends breaks up search terms into thematic categories that are a good reflection of media coverage trends; see environment (”Grass is Always Greener”) and crazy celebrities (”Celebrity Downslides”). This year they also added a list of searches on social bookmarking site del.icio.us, which are slightly more celebral than their top 10 overall list that is topped (again) by the venerable Britney Spears. Here’s that top 10 overall list (via WebProNews):

1. Britney Spears
2.WWE
3. Paris Hilton
4. Naruto
5. Beyonce
6. Lindsay Lohan
7. RuneScape
8. Fantasy Football
9. Fergie
10. Jessica Alba

Yesterday TechCrunch reported that Google exec Marissa Mayer revealed 2007’s fastest-growing search terms on the Today Show. Here’s the list she announced:

1. iphone
2. webkinz
3. tmz
4. transformers
5. youtube
6. club penguin
7. myspace
8. heroes
9. facebook
10. anna nicole smith

Note the relative absence of celebrities in Google’s list when compared to Yahoo’s. Google’s list is fundamentally different from a top 10 most popular list by definition, because it is compiled by determining the most popular search terms for 2007 and seeing how much queries increased compared to last year (at least, that’s how Google determined 2006 fastest-growing terms, TechCrunch notes). Yahoo’s trend list methodology sounds similar (emphasis mine): “To come up with the Top Trends of 2007, we analyze search queries based on a number of factors, including absolute volume and growth versus previous periods, to see which themes and trends bubble to the surface”; the continued presence of Britney Spears on their overall list, though, suggests that absolute volume is still a dominant factor in their equation. The end effect on the overall list is that Yahoo’s users end up looking a little dumber than Google’s users – perhaps this is why the overall list isn’t included on Yahoo’s trends page (in fact, I couldn’t find it on Yahoo though it was available on TechCrunch and WebProNews), though I’m sure the overall most popular list from Google would show similar queries.