Pretty simple in concept, actually. We will have one common UI and front end that calls either an Ethereum or NEM back-end depending on the token the user decides to use. Users will select their token early upstream in the transaction process by clicking an NEM or Ethereum button, that then calls the separate back ends. Of course, this is easier said than done, but just to clarify, a user obviously will not be using the Ethereum and NEM blockchains simultaneously for a given transaction.

Stay tuned for our official Bitcointalk ANN to come in the following weeks as we iron out details for our crowdsale.