The SEMNE organization landed an incredible opportunity last week with a guest lecture from Dan Crow. I've seen Dan speak once before several years ago and was shocked by his overly secretive conduct. Thankfully, Google, and apparently, Dan, have changed a lot since then. He had some remarkable things to share with the SEMNE group and, thanks to Jill Whalen's post (Getting Into Google), the rest of us as well:
We were also treated to some additional tips that many people may not have known about. For instance, did you know that you could stop Google from showing any snippet of your page in the search engine results by using a “nosnippet” tag? And you can also stop Google from showing a cached version of your page via the “noarchive” tag. Dan doesn’t recommend these for most pages since snippets are extremely helpful to visitors, as is showing the cache. However, Google understands that there are certain circumstances where you may want to turn those off.
Google is coming out with a new tag called “unavailable_after” which will allow people to tell Google when a particular page will no longer be available for crawling. For instance, if you have a special offer on your site that expires on a particular date, you might want to use the unavailable_after tag to let Google know when to stop indexing it. Or perhaps you write articles that are free for a particular amount of time, but then get moved to a paid-subscription area of your site.
Lastly, Dan mentioned that Google still isn’t doing a great job of indexing content that is contained within Flash and/or AJAX. He said that you should definitely limit your use of these technologies for content that you want indexed. He provided a bit of information regarding Scalable Inman Flash Replacement (sIFR), and explained that when used in the manner for which it was intended, it’s a perfectly acceptable solution for Google.