Ouch, that's not good. Perhaps that's something that could go on the wishlist for a future version. I'm looking at this from a customer service and support perspective. Here's the scenario ...
eCart returns and displays the incrementing OrderID on the Confirmation page.
eCart does not return and display the PayPal transaction ID on the Confirmation page.
PayPal's e-mail message to the buyer displays the PayPal transaction ID (9999-9999-9999-9999).
PayPal's e-mail message to the buyer does *not* display the eCart OrderID.
Neither one has the information needed to fully support an incoming call for help. If they have their eCart OrderID, great. If they don't but they do have their PayPal transaction ID, then not so great.
Having and storing *both* in the database means I should be able to find any Order any of my customers need supported. Granted, I understand I can still find their Order given their name, address, date of sale and so on. But if you guys could look at this for a future release, that would be great.