Topic: My rankings have dropped. How do I find out what’s wrong? – Quick Answer: Start with site:mysite.com, check for malware, check Webmaster Tools. Try the Webmaster Forum. Is it just your site, or lots of sites?
Topic: How do you rate links from sites like Twitter and Facebook? – Quick Answer: Google treats all links the same
Topic: Uncrawled URLs in search results – Quick Answer: We found a link to the page but didn’t crawl the page itself
Topic: Should I use underscores or hyphens in URLs? – Quick Answer: Hyphens
Topic: Should I use the Vary HTTP header on URLs that redirect based on user-agent? – Quick Answer: Yes, it’s still used by Google though maybe not other services
Topic: Do I need to set state-level geographic targeting in Webmaster Tools? – Quick Answer: You can’t target at state level