How can I manage Intent association with Apps? When the system emits an Intent for which you have multiple apps that can handle the intent, a dialog opens to tell you which application you want to use with that intent.

Is there a way to see what these associations are, and clear them?

If there is no app or interface to do that, do you know of an API to access these associations?

EDIT: When I said associations, I was thiking of the "late-bound" associations. For example, when I open a link and I have multiple browsers, an intent is fired saying "view link", and I choose "always use that application"; what can I do if, after some time, I would prefer to use another application for that intent?
I believe it's a no to both those questions. Yes you can clear default associations only if you know which app is associated with with Intent (you will still be prompted with the dialog asking you which app you'd like to use with the current Intent). 

Apart from that there is no way to clear associations. They are hard coded inside each app, there is no way to remove them.

UPDATE: To answer your edited question head to Settings > Applications > Manage applications find your application that you chose as your default app for that intent, click Clear defaults