A deal is in the works to add a repeal of Don’t Ask, Don’t Tell to this year’s Defense Authorization bill, the method by which it was originally made law. It’s not clear that the votes are there in the House to do it, and if they aren’t there this year they’re unlikely to be there in the next Congress. It would not be subject to filibuster in the Senate.
The repeal is limited in one sense. It does not ban discimination against gays in the militery. It returns the status quo ante DADT in 1993 when the president had sole authority to set military personnel policies on gays. The difference is that now the president has promised to reverse the old policy after a study is issued in December on how to implement the change.
In theory, the next president could reassert the ban. But that’s very unlikely to happen once gays are serving openly. Liberalization of anti-gay public policy tends to be governed by one-way ratchet. Plus, the experience in other countries has been that allowing service by openly gay personnel presents no real problems for recruitment, retention, or discipline, and controversy about it quickly subsides.