Feature request:
For marketing campaigns its necessary to know if a mail has been opened or not.
Some e-mail applications, such as Microsoft Office Outlook, employ a read-receipt tracking mechanism. The sender selects the receipt request option prior to sending the message, and then upon sending, each recipient has the option of notifying the sender that the message was received and/or read by the recipient.
However, requesting a receipt does not guarantee that you will get one, for several reasons. Very few e-mail applications or services support read receipts, and users can generally disable the functionality if they so wish. Those that do support it aren't necessarily compatible with or capable of recognizing requests from a different e-mail service or application. Generally read receipts are only useful within an organization where all employees/members are using the same email service and application.
Depending on the recipient's mail client and settings, they may be forced to click a notification button before they can move on with their work. Even though it is an opt-in process, therefore, a recipient may consider it inconvenient, discourteous, or invasive.
Read receipts are sent back to your Inbox as e-mail messages. Additional technical information, such as who it is from, the e-mail software they use, and the IP address of the e-mail server is available inside the Internet headers of the read receipt.
Note that the IP address shown might not be a public IP address, and most likely will be the IP address for the Internet service provider the recipient uses for their internet e-mail service.
The technical term for these is MDN - Message Disposition Notifications, and they are requested by inserting one or more of the following lines into the email headers: X-Confirm-Reading-To: Disposition-Notification-To: or Return-Receipt-To:
On the same page you have:
"E-mail marketing and tracking
Some e-mail marketing tools include tracking as a feature. Such e-mail tracking is usually accomplished using standard web tracking devices known as cookies and web beacons. When you send a tracked e-mail message, whether it's a simple text message or a graphical html message, the e-mail marketing system may embed a tiny, invisible tracking image (a single-pixel gif, sometimes called a web beacon) within the content of the message. When the recipient opens the message, the tracking image is referenced. When they click a link or open an attachment, another tracking code is activated. In each case a separate tracking event is recorded by the system. These response events accumulate over time in a database, enabled the e-mail marketing software to report metrics such as open-rate and click-through rates. E-mail marketing users can view reports on both aggregate response statistics and individual response over time."
which is the only way as-far-as-i-know that email tracking can be done. Return receipts are not reliable. Most email clients have an "ignore return receipts" option. There's a "send return receipt automatically" option too but that's rare.
The above tracking method is also not 100% reliable since most email clients nowadays hide images from remote addresses unless the user really wants to see it. I rarely do.
Click tracking is a better approach but then you have to have something valuable inside the email so your customers will actually click a link which will have a unique ID for the mailing + customer.
Since openERP is very likely going to be behind a firewall, these options are unavailable to it anyway. I think it might make sense to find a free online tracking solution and build a module for it that may/may not integrate with poweremail.