Although the name is content management system, I found out that they can potentially be one of the strongest tools an online marketer can have access to.
engaging your existing traffic is more important than attracting new traffic
you should only atract new traffic when you are happy with your conversion rates
"Product" is still one of the 4 P's i.e. what the product is, is one of the most important aspects of the marketing
The more you can tweak your product, business rules, layout, the more control, speed and efficiency you gain in your marketing
Drupal gives you that.
Path: allows you to simply change the URLs of your pages manually from within each post
Pathauto: allows you to create an automatic system for generating URLs based on certain "tokens" you specify. For example, if the default URL structure is /prodcuts/123 you can change it to cameras/sony-digital.
Page Title: You can simply change the title of your pages, which is one of the most important factors in determining the relevancy of a page.
Here is a more detailed analysis of Drupal's SEO modules.
Statistics / Measurement:
Statistics: general statistics on traffic, visits, top referrers and error pages. Although most of this is more meaningful through your web analytics package, some (like top "page not found" and "access denied") help a lot in understanding where some bugs or misunderstandings are.
Google Analytics Module: Makes it easier to install it and helps with automatically doing some advanced stuff like trakcing outgoing links, file downloads, and similar things.
Drupal Modules for marketing
Statistics / Measurement Modules
Behavioral Targeting Modules
CRM / Notifications Modules