After receiving a comment from Michael (assuming he is from about a new email client I decided to give it a quick try and here are some of my observations:

* Works by sending your message as an image or hosted file, that changes to a blank image based on user settings (for each message) such as: time from first open, number of opens, or time from delivery.

* Works great if the recipient reads HTML messages with Images turned on, Inversely it doesn’t work with Text readers, so some business or technical users will encounter issues with this.

* Update incorrect items in email that has already been delivered. Nice feature but open for abuse or fact changing. What better way to deal with things like insider trading – an email that sends and deliverers secret information and then becomes a blank message 2 minutes later… or other industries where email content is archived under policy or legislation and stored for future review or investigations. The Terms of service (TOS) talk about preventing abuse and terminating accounts when proof is provided that someone has abused their policies, but without proof there is only a blank message to base judgements on.

Over all I think some home based users will consider use this, but there is a lot of potential for bad things to occur in the business world.