In recent months we have added many performance improvements to the platform. Many of these improvements come via caching techniques. While the details are somewhat technical, CE now include multiple levels of caching from the server level to the application level. The caching takes place both on the web site (ie "front end") and within the administration section (ie "back end") of the system.
While these improvements will continue, we have already seen a dramatic improvement in page load speed as a result.