Just a suggestion for the flow shared by Mark. I suggest we should not use the Anonymous filter. Assuming, if any user who already has a mucnkcin cookie (for other Marketo account) visits your webpage for the 1st time, he will be considered as a repeat user, since Anonymous will be false for him.
If we don't use this filter, all the users will be tracked and at a later stage when they become known leads, their past record will be updated in Marketo for frequency of visits.