According to PWTorch.com, with Shawn Michaels returning for a match at Vengeance, the DeGeneration X revival angle is still on.

Michaels will work a tag match with Triple H at that PPV and then keep a limited schedule until Summerslam to continue the faction for the short-term. Following Summerslam, he will take several months off to undergo knee surgery.

This news should further indicate that WWE presently has no plans to make the DX faction a long-term staple.