So your earnings as a Devtome author aren't really earnings at all, they are just like Dragon Kill Points in an RPG, the Devtome uses them to measure the relative contributions of the team.
Your earnings however as a seller of devcoins for fiat on an exchange are earnings, as are your barter earnings if you barter devcoins for something real of real value such as a cup of coffee or a meal or rent or whatever.
I am not licensed to practice law on this planet though so check with your own local licensed practitioners.
-MarkM-
Yeah, that is my take on the whole matter. How would one even figure out a price on your holdings of Devcoins if the price is different on each exchange? Not to mention they could just disappear into thin air almost overnight.
I am only going to report my earnings that I convert to Bitcoin and cashout to my bank through Coinbase.
Remember fiat is the only thing taxed not crypto. If you sell back to crypto your taxed. Unless they make bitcoin legal tender and you can pay tax with it then depends where you live i think in Uk some placed wanted to do this.