A further related bug:
The Sun Paladin escort quest offers points in "Chant of Fortitude" or "Chant of Resistance". As these abilities no longer exist, accepting one of those rewards rewards you with nothing.
Uh what? If you don't have the talent it gives you it. If you do i think it increases the mastery of that specific chant (if it wasn't bugged)
I have an Anorithil. The Chants category no longer has "Chant of X" talents. (I was also under the impression that the effect of the chant was different from the one described on my action bar.) However, my quest log says I selected the talent Chant of Fortress.
On rechecking, it does look like I do actually have 2 points in Chant of Fortress as compared to 1 in the others now... and it appears to have dropped down to the 0.8 multiplier. The hidden talents make sense now that I think about it, but it's definitely not behavior one would expect, I'd say.