We’re on our 3rd CDN trial, again as noted this is focused on improving the site image load performance time. As usual testing was done before flipping the switch on. Our particular interest is if European users are seeing faster page loading time with this feature. Please comment with your feedback.
Per the last trial, we have for some time now implemented a number of well-known tricks to optimize image delivery. This includes spreading the load between four hostnames, as mentioned by commenter dweazy – along with proper cache HTTP response headers, stripping JPG metadata comments.