Current State of affairs:
Gmail currently asks you before showing images in emails. Google, like other companies that provide email services, does this to protect the user from senders who might try to use images to compromise the security of your computer or mobile device.
What is Gmail changing to:
Gmail has recently made changes so that all images will be served through Google’s own secure proxy servers. Images are normally served directly from their original external host servers, but this change means Google can be responsible for the security of images received in emails on its service.
Simple: your email messages are more safe and secure, your images are checked for known viruses or malware, and you’ll never have to press that pesky “display images below” link again. With this new change, your email will now be safer, faster and more beautiful than ever.
Our initial testing of this change in Gmail confirms email rendering has sped up considerably. Lightening fast in fact.
What does this mean for email marketers?
Image caching lowers the ability to track repeat opens of each email, but with Gmail turning images on automatically it will mean reporting should be more accurate when tracking unique email open rates.
In the past by leaving images turned off, Gmail had been allowing subscribers to open and read emails without downloading the tracking pixel we embed is each email. So these opens were invisible to you. Now Gmail are displaying images automatically, the previous invisible opens should now become visible.
So we see this as a win lose situation. We expect open rates to be more accurate, but repeat opens to be less accurate.