Holy crap. If I'm reading this right, this basically destroys all pixel tracking, so no more email open stats, no nothing.
I tried to opt-out of external content in Settings > General but unfortunately it's still loading images.
If a piece of content is delivered to me via the mail, I should be able to open a cached version as many times as I want without any request to the remote server.
And the cached version can be built for me by my mail system, which by ALWAYS fetching the resources protects me.
As a question of what SHOULD happen, I thinkread receipts should be voluntary.
Agreed, and not even the server has to do that, any good e-mail client could (as it seems Gmail is now starting to do).
I'd really hate to be in the bulk email business today. Perhaps google will sell them back the data they used to create themselves.
Alternatively, if you're not the sort of company that naturally engenders an active community, Twitter. It's not perfect, but it's a far better experience for customers who may want to keep up with what you're doing but don't want a new email to delete every week.
httpurl/image.jpeg?email=your.email@gmail.com