As you may know – I’ve been a fan of Sitemaps for years:
On SEOmoz, chenry wrote about an experiment he ran to see if submitting a Sitemap to Google and Yahoo would decrease the time it took Google to crawl and index the page. As he said – the results were amazing!
chenry said:
The results for this blog were amazing! When a Sitemap was submitted the average time it took for the bot to visit the new post was 14 minutes for Google and 245 minutes for Yahoo.  When no Sitemap was submitted and the bot had to crawl to the post, it took 1375 minutes for Google and 1773 for Yahoo.  The averages were calculated on 12 different posts, 6 with Sitemaps being submitted, and 6 with the Sitemaps not being submitted.
Did you SEE that – 14 minutes vs 1375 minutes (22.917 hours) – just to get a site CRAWLED – much less INDEXED.
This isn’t news to me, but it is really great to see some actual facts and figures so well graphed and documented – kudos to chenry.
In the comments section for this post, Rand Fishkin (head of SEOmoz ) responds to a query about an old post indicating that Rand did not view sitemaps as useful:
With regards to my post – I actually no longer hold that opinion, so I’m going back to edit the piece. I’ve actually seen the results of Sitemaps be so positive for so many clients that despite the loss of visibility into architectural issues, I tell everyone that 99% of the time, you should be submitting as one of the first actions in your SEO campaigns.
Personally, I have ALWAYS found sitemap.xml files to be of great benefit – virtually to the point of “if you only do ONE thing – DO A SITEMAP.”
I’m not tracking like chenry did so well in his experiment, but I am seeing benefit from the sitemap and feeds I created and submitted for another new site I’m involved with (was crawled almost immediately, and was indexed in Google within 24 hours).
I’m off to go pat myself on the back a bit for being so clever…, and maybe build another sitemap file or 2. Â 
