Interesting article from Wired News on Yahoo's mistakes in the SE Market.
More interesting however, is SEOmoz's opinions on why they believe google won out:
Google's clean UI was revolutionary and attractive; it's still one of the elements consumers cite most about their use of the engine.
Purity of function
Google's concentration on search (at least in the early years) made them first and foremost a search engine in people's mind. Yahoo! was a directory, a portal, an email service, etc. and, oh yeah, also an engine.
Appeal to Geeks
Google appealed to tech geeks - the people who set the home pages on computers around corporate offices and at home for Grandma. When thousands of influencers in a field become obsessed with a product, it achieves mass popularity (just look at Apple).
Google's marketing was nearly invisible at a time when invisible, viral marketing was being embraced by consumers, particularly those in the web world.
Early quality advantage
Perhaps no single factor is of greater import - Google's early lead in quality was so large that switching to Google was an obvious choice. In my opinion, this was Yahoo!'s biggest failure - letting Google return more relevant results. The funny part - I honestly can't say whether senior management was responsible for or could have controlled this factor. It could be that Google simply had a few people with better ideas and all the hiring and R&D in the world couldn't have saved Yahoo!.
Being a media darling made Google incredibly well placed to get early interest from even the stodgiest of users. And, with no need to market or advertise (since press releases on the average consistency of Googlers snot got more coverage than a major media play from Yahoo!), Google could spend that money in R&D to continue their edge.
What do you think? Did Yahoo! and Terry Semel really falter strategically, or was the deck simply stacked against them for the past 5 years?