Comment 19 for bug 199069

The profile pages are currently delegating to the non-human readable identity URLs. The problem is that if you log in with your profile page, then the RP records your profile page as your identity rather than the identity it delegates to.

If you change your Launchpad nickname, anyone would be able to take over accounts you'd created on remote sites logging in with your LP profile page as an OpenID.

Even when we've switched to the human readable identity URLs (which should address Caroline's concerns), this bug will still be an issue.