The single most important component of your web-based business is your website's conversion rate. What is a conversion?
This is an important list of common ways to increase conversion. I might move cart work up to #2 or #3, but I can understand why the author has it lower down. Shopping carts are painful to change. Touch your shopping cart now and you are NUTS since the biggest deadline we all have is around the corner (12.25).
Here are some quick fix conversion additions I would make after $30M in online sales over seven years:
* Free Shipping All Orders, All Shipments (don't fight it).
* Better Email Marketing (see http://www.bronto.com tips).
* Better email tool (Bronto is best).
* FASTER website (Offload images/video to Akami or similar).
* More SOCIAL (Facebook LIKES, G+ and Twitter everywhere).
* More SOCIAL (bring my friends into my shopping experience).
* REVIEWS - (critical for ecomm and must have some bad).
* Review the Reviewer - (makes reviews trusted).
* Coordinate social, email, catalog and website (always friction).
* Keywords In Navigation, Titles and H1 (can always be better).
* Breadcrumbs (great spider food).
* Merchandise and simplify internal search (big bucks here).
Pick any 3 from the list above and your website's sales will increase before this Christmas. Do them all before Christmas and I owe you lunch for a week (lol).
Good luck. Try to get some sleep between now and Valentine's Day :).