You've got no guarantee about when that image will be loaded by their proxy, making statistics next to useless.
Google could prefetch those images. Even if the initial tests seem to indicate against this, they can change this on a whim, or they could prefetch with a delay, or they could prefetch only a percentage of those images, depending on ever-changing heuristics. The only useful info advertisers would get from this is that the email was sent to a Gmail account.
Even if they don't prefetch, they can detect duplicates, especially from links coming from domains known to generate tracking pixels and there's nobody else that could do this better than Google. They can also get rid of images that aren't visible to the user (e.g. transparent or white or light gray pixels, or images that are too small to be a part of the content). Tricks like generating images with unique content only work for images with actual content to show.
And it significantly raises the cost of email campaigns too, just as with spam. I don't have spam hitting my Inbox these days and that's not because spam has become impossible. Light spam (e.g. promotions from companies you've got a relationship with) have been moved in the Promotions tab. And I can't remember the last time I've seen real spam hitting my Inbox.
All in all, I'm happy that they are introducing this feature. It's better for regular folks or for me - you know, the kind of people that always click Show Images, because promotional messages are hard to read otherwise (on purpose).
I do hope they provide the option to turn it off. Google is pretty bad at providing choices these days.
If you are sending a marketing email to a person, an easy image that has unique data is their name. :) And I didn't even think hard on this. Pretty much any content that could have been easily done as text is easily done as a "dynamic" image.
Now, they can detect duplicates, but only after they have gotten the contents. Unless I am mistaken on anything. (highly possible.)
Such instances can be detected (e.g. if you see 100 emails with the same HTML, but with image URLs that are slightly different). Google can then prefetch those images or it can re-enable the optin for displaying just for those emails.
If I were to do email tracking, I would just filter the GMail accounts out of the statistics, because you can't be sure of when GMail's proxy loads those images and what you're interested in is the conversion rate (not in the total number of people that opened their emails, you only care about totals for emails sent and clicks). But a service like MailChimp is not interested in doing this, because MailChimp is a third-party that's interested in showing big numbers to their customers.
And putting these numbers aside, the privacy issues related to IP tracking, or the security issues are gone. So I think this is good.
Certainly whac-a-mole. Didn't mean to imply otherwise.
For myself, no need to filter them out without evidence. Keep a few controlled accounts to periodically try and see what the delay is. And get extra suspicious if all images are opened at once on a mass send out.
Google could prefetch those images. Even if the initial tests seem to indicate against this, they can change this on a whim, or they could prefetch with a delay, or they could prefetch only a percentage of those images, depending on ever-changing heuristics. The only useful info advertisers would get from this is that the email was sent to a Gmail account.
Even if they don't prefetch, they can detect duplicates, especially from links coming from domains known to generate tracking pixels and there's nobody else that could do this better than Google. They can also get rid of images that aren't visible to the user (e.g. transparent or white or light gray pixels, or images that are too small to be a part of the content). Tricks like generating images with unique content only work for images with actual content to show.
And it significantly raises the cost of email campaigns too, just as with spam. I don't have spam hitting my Inbox these days and that's not because spam has become impossible. Light spam (e.g. promotions from companies you've got a relationship with) have been moved in the Promotions tab. And I can't remember the last time I've seen real spam hitting my Inbox.
All in all, I'm happy that they are introducing this feature. It's better for regular folks or for me - you know, the kind of people that always click Show Images, because promotional messages are hard to read otherwise (on purpose).
I do hope they provide the option to turn it off. Google is pretty bad at providing choices these days.