How can linking remain a major part of a search algorithm when the majority of Internet users are unable to post a ‘followed’ link on the World Wide Web? For example Twitter, Facebook, wiki etc. are all ‘nofollow’. It seems only a very small percentage of links count. Ed, Caribbean

Following your interview with Eric Enge – you mention about “If Modified-Since.” We worked on many websites whereby the actual file timestamp doesn’t change but the content does as the pages are database-driven. How should we deal with such situations? Tommo, London, UK

Is there a good way to kick off a feed in Google Reader by doing something like temporarily making the feed include a whole bunch of old content? Is it desirable to do something like that? Stephen B, Belton, MO