An important aspect of Drupal SEO is the robots.txt file. Drupal 5 was the first version of Drupal that came with a robots.txt file, but it still needs some modifications.
This is part 3 of a case study on how Drupal.org could be further optimized for search engine rankings.
This article is part two of the series on optimizing Drupal.org for search engines.
This tutorial offers some advice on how to optimize Drupal.org for search engines. This is part one of a series.
This tutorial shows you how to use Drupal's Pathauto Module along with taxonomy to automatically generate nice URLs on your Drupal site.
Google Engineer Matt Cutts talks about canonical home page URLs on his blog. The concept is basically this: