Best of Google Webmaster Help videos

Over at SEOmozBlog, Dr. Pete informs that there are 200+ Webmaster Help videos on YouTube featuring  Matt Cutts, Google's most visible anti-spam engineer. Occasionally, some Google secrets slip out during these videos. He watched 70 of the videos posted in 2010 & gathered some unusual facts.  Excerpts -

• Google does not use the keywords meta tag for ranking. Meta description still has value for other reasons
• Cross-linking 3 sites probably isn't a big deal, but 30 or 300 could likely get you into trouble.
• ...footer cross-links are often low-value
• Google does not guarantee that pages in your XML sitemap will be indexed.
• Indexation has a lot to do with your authority and trust – an authoritative site will get more love from the crawlers, plain and simple
• Matt (Cutts) says: "Most people can switch their IP address and never have any issue whatsoever."
• As long as your domain name and hosting country stay the same, switching from one reliable host to another should have no SEO impact.
• page speed...would be one of over 200 ranking factors.
• Google makes a change to the algorithm on the order of ONCE PER DAY.
• These changes may be batched and rolled out in chunks, but another video confirmed a number of roughly 400 algorithm changes in 2009.

Related:
What's in Google's secret PageRank sauce?

Summaries of Google Webmaster Central YouTube videos

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