Really?  Are you saying PayPal is not profitable and the lack of profitability is due to the costs of phone support for noobs forgetting their password?<p>Don't throw ARPUs at me.  Either they are profitable or they are not.<p>I can certainly understand the argument that users of other sign-on systems "may" remember their passwords better than PayPal, but what evidence do you have of this?  What extra margin of increased password remembrance makes for a more profitable model?