The Hardy's contracts with TNA are due to expire this week and Wrestling Observer Radio's David Meltzer reports that it's "certainly in the ballgame, if not likely" they will go back to WWE.
Apparently Jeff Jarrett coming back to his old promotion has made it more likely they are leaving. That may be due to them not having the same level of creative freedom with the new change in management.
However, if the brothers returned to WWE you would expect them to have much, much less freedom than in TNA. It's doubtful that Vanguard 1, Senor Benjamin, King Maxel and even Reby would be joining them in any form.
This would be a huge blow to TNA if Matt and Jeff leave.
Not only did the company just lose Drew Galloway, but the Hardys have their tag titles and are involved in a big angle where they take on teams from other promotions.
Nothing is set in stone yet, as the brothers are still negotiating with TNA. We'll find out very soon what direction they're heading, as the next set of TV tapings take place on Mar. 5.