It looks like the Ubuntu Software Centre can only work with static license keys. Will it also support dynamic license keys based order details (name, date, email, etc)?
The situation here is that some applications use user-details to create the license making it unique. For example, you might use the customers e-mail address as an input to the hash.
We've been asked for this feature a number of times so we're certainly aware of the need. However, each developer uses a different process to generate their licenses. Consequently, we'd either need to provide a system within Ubuntu (ie a library) or some sort of API integration within the Apps portal. Either of these would be complex undertakings.
So, for the moment it's going to be static licenses and we'll probably concentrate on mechanisms like e-mail notification.