How Google and Yahoo handle redirects

Great article at SearchEngineWatch "Revisiting Hijacking & Redirects: Moving To A Solution" explains how Yahoo and Google handle redirects.

Yahoo:

• 301 Permanent Redirect
  source-domain –> target-domain = target-domain URL kept and used for listings
• 302 Temporary Redirect
  source-domain –> target-domain = target-domain URL kept and used for listings
• 301 permanent redirect
  root-page –> deep-page = rootpage kept and used for listings
• 301 permanent redirect
  deep-page –> other-deep-page = the page directed to is used for listings
• 302 temporary redirect
  deep-page –> other-deep-page = the redirect is NOT used for listings

Google:

• With 301 permanent redirects, Google uses the URL of whatever is pointed at.
• With 302 temporary redirects, Google generally assumes that the page with the highest PageRank score is the URL that
  should be used in search listings.

And don’t forget that search engines’ redirect policies are subject to change.