Conversation not registration

My friend Eric M came to work with a great idea. Instead of registration to a website – where a punter is asked a load of questions in a form. You engage then in a conversation and ask for only the information you need at the point that seems relevant to the user. For example if it’s a game site you ask for a name to use so they can play a game. When the player wins you ask for an email address so you can send them their prize or so they can share their score. When they lose you ask for their email address to send them more tokens or chips so they can play again. Hence my condensation of this idea as a conversation instead of registration.