It says right in the article Rebels and it's prequel novel are canon.
But these are both upcoming projects. So far the only thing that has been confirmed to remain as canon is Clone Wars CG.
So I guess, Ryloth has a day/night cycle from now on. Other than that, I think this change is good for the franchise and our game, especially since this doesn't necessarily mean that Thrawn, et al never happened: what can be salvaged from those books in the advent of the sequel trilogy most likely will be, as writers are still free to pull from that material. All that's different now is that they have a Story Team present to minimize canonical discrepancies, and I like that. I hated not knowing what to believe about Ryloth for the time since its appearance in CW. It's nice to have closure.
EDIT: A better example than Ryloth I just thought of, is the half-a-hundred people including Kyle Katarn who stole the Death Star plans. Leeland Chee won't have to bend the canon over backwards to make sense out of that sort of thing anymore. There'll be one "true" story of how the Rebels stole the plans, and that's it. Way less confusing.
Edited by MarthWMaster, 27 April 2014 - 04:38 PM.