This is better than a pure dollars-based elite program (which is what the airlines really want), but Delta continues to miss the point: US and UA went bankrupt, and DL has a golden opportunity to entice their disillusioned frequent fliers.
Instead, they stir a major controversy. How many US and UA pax will be tempted to switch? By my reckoning, not as many as would have under the "old" DL program.