The top CMS for ecommerce is a difficult question to answer, as you have not defined your ecommerce environment. However there are some foundational considerations to be understood for whichever type of environment or business stage that you are involved with. The envelope please:
· Built in stable and reliable structure.
· Open source platform
· Ability to adjust existing features and add new ones
· Shopping cart, catalog management, search, checkout and administration functions
· Can be hosted anywhere
· Add-ons available from community members
Because of our business stage, we have chosen WordPress and its more than6 million downloads. Moreover WP e-Commerce is one of the most popular amongst those many downloads.
I tried answering your question with the best information for you given your shared information and my experience with CMS. I would suggest that you visit the WordPress site and evaluate whether or not it would be able to meet your needs. Additionally, suggest that you evaluate the other open source CMS suppliers, such as Zen Cart or Magento, to make further comparisons about which ecommerce CMS platform is best for you.