In a blog entry from the Gatsby Days 2020 event in Los Angeles, Greg Thomas highlights a presentation by Trevor Harmon, a front-end web developer at Shopify, on using Gatsby and Shopify to create fast e-commerce websites. The post underscores the importance of website speed in online retail, noting that even a one-second delay in load time can lead to a 7% decrease in sales annually. Trevor's presentation offers a comprehensive guide for setting up a Shopify store and integrating it with Gatsby to build quick-loading e-commerce sites, including steps to pull data into Gatsby, create pages, and implement a Shopify plugin for checkout management. The event, initially held in-person, is set to continue as a virtual gathering, allowing a wider audience to access the insights shared by experts like Trevor Harmon.