Duda would have made the league minimum next year with arbitration starting after 2014.
However, by qualifying as a Super Two, he now will be eligible for arbitration next season.
In either case, he will not be eligible for free agency until after 2017.
This is not a huge deal, but it's worth noting. The significance of this will really be determined by how well Duda performs this season. He's on pace to hit 35 HR with a .450 OBP. If he does this, he'll be in store for a nice raise, I'm sure. But, that will also mean more money in subsequent years starting at that rate. The Mets will have significantly more money to spend on new talent after this season. And, while I'm sure they're happy to reward one of their better young players at that point, I'm sure they'd also have preferred to keep him earning the minimum to keep money in the budget for new talent as well...