The new Yahoo! Search Crawler (Slurp)
"We launched a new Yahoo! Search Crawler, Yahoo! Slurp earlier this week. In addition to crawling the Internet faster, our new crawler is more efficient at visiting websites. As a result, site owners will notice as much as a 25% reduction in the number of requests and bandwidth consumed by the crawler. [...]
With this change of behavior in the crawler, you may see some shuffling of the pages that are included in the index and some changes in ranking as well."
Google's Matt Cutts talks about SEO on Google Video
"This is my personal opinion. The views expressed on these pages are mine alone and not necessarily those of my employer. [...] I wanted to make a video so that I could give a little more detail and nuance than you’d get from reading a sentence or two."
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