Logging in to Joomla - Different scenarios (need feedback!)

There's been 2 posts recently about a scenario that some people are unsure about, and would like to have your feedback on the suggested fix. It's not exactly a 'bug', but can see how people would think it's not operating as it should be.

Background:
Creating a new Joomla user:
When we create a Joomla user using their Facebook information, we 'map' that user's Facebook ID to their Joomla ID. This way, when they return and log in with their Facebook credentials, we automatically log that user into the Joomla side. No real problems there.

Linking a FB account to an existing Joomla user:
When a user logs into Joomla with an account they already have, JFBConnect shows a "Connect this account to your Facebook account?" text. If you click that, then your users are mapped. Upon returning, you can use your FB credentials to log 'both' your users in.

Problem:
If a Joomla user (created through their FB account) user updates their Joomla password and returns to the site and logs in to that Joomla account (NOT logged into FB), JFBConnect still shows the "Connect this account to your FB account?" text.

- If they log into FB now with their original FB account, nothing changes.. the mapping stays the same, all is good.
- If they log into FB now with a different FB account, their mapping is updated (which could be bad). The joomla user they had no longer has a FB account associated with it, and the Joomla user their logged in with is now mapped to 'this' FB ID.

Reasoning:
The reason that users are allowed to update their mapping is in case a user has a Joomla account on your site (lets say for 5 years), and comes one day and accidentally logs in with their FB account. That creates them a 'new' Joomla user. If we didn't allow re-mapping, that user would have to make a choice as to which user to continue using (or you as the admin would have to fiddle with some things to re-map them).

Generally, users only have one FB account, so this issue isn't that bad. It may create some extra Joomla users on your site, but really not pain your users.

Solutions:
1) Leave it as is. Allow you to change the text in the Login module to say whatever you want so the "Connect this account to FB" isn't confusing.
2) Lock 'mappings' so that once a FB ID is used, it can't be reused. We'd update the login module to check the Joomla user and see if the user already checked in has a mapping and just not show that text.
3) Lock mappings. If a user performs a FB connection, come up with a way to ask a user if they already have a Joomla account, and want to use that for their mapping.
4) Your suggestion!

Please keep in mind, one of our highest goals with JFBConnect is making it easy to use (and code). Having 20 options to allow each method isn't really an option. So we'd like to get some feedback for a few days, then make a decision. We don't think that any path will be overly difficult, but want to make sure it's the best.

Thanks for your input!