Meanwhile, over at UIE:
'...having a usable web site is not always enough to convince users to transact. Even if a user can complete a transaction on your site, doesn't mean that they will transact.
To be successful, sites must go beyond Usability by focusing on Persuasive Design. They must motivate users by taking advantage of persuasive tactics that will make them take action. The most persuasive web sites focus on making users feel comfortable about making decisions and helping them act on them.'
Continue reading here.