I've been banging my head for the past several hours and finally broke down and called Marketo support. We need to track click activity on a Marketo landing page. The use case is an RSVP page with an "Accept" button and a "Decline" button. Based on what link the user clicks, they will either receive a confirmation email or be sent to a "sorry you can't attend" landing page. Apparently this is not possible. At this time, there is no way to use the trigger "Clicks link on web page" when Marketo landing pages are being used.