There's currently no way to know if a Munchkin _mkto_trk session is associated with a named lead.
A session can change from anonymous to named via a number of different methods (link click, form fillout, deliberate Munchkin assoicateLead() call) and it is not feasible to catch all of these possible points. And obviously if a session is already associated at the time you check, there won't be anything to catch.
Segregating anonymous and named leads is invaluable for analyzing your revenue cycle from different angles, for example by logging to Google Analytics with a custom dimension ( visitor type = anonymous or named ).
I requuest that either Munchkin get an additional munchkinFunction, 'isAssociated,' that returns true/false.
.png)