As we learned on the forums a while back, Champions will receive "Ardour," a new stance which strikes a balance between offense and defense. Previously, they had only the mostly-useless default and the haphazardly offensive Fervour stances until late in life. Glory, the defensive stance that they presently get at level 46, will be moved all the way back to level 30, because the 30s are arguably when Champions are most often called upon to tank.
The class will also get some major revamps to its Legendary Skills. If you want all the minute details, Turbine reps went even deeper on the official forum. We Champs have a lot to look forward to!