Maxperson
Morkus from Orkus
That's a bit tricky though isn't it? Wasn't the Silmarillion at least in part written by Tolkein's son? Yes, it uses Tolkien's material, but, his son did write chunks of the book. Since we don't really know what changes were made by Christopher Tolkien, how can we call it "canon"?
For my part, I'm okay with Christopher filling in the blanks and deciding which of the multiple different canon stories his father most likely intended to be official. He inherited the control of the setting, just like WotC inherited them from TSR when it bought D&D. If the setting belongs to you, you can make changes to canon and have them be canon.
And again, there's the specific issue of Dragonlance. Some of the changes to the DL setting were done in 3e by Margaret Weiss Productions, which had the license for the DL setting. Note, not all the changes were done by Margaret Weiss either, as there are a number of other authors involved. It's a pretty fine line to draw.
I mean, how many Batman authors have there been? How many Conan? Does that mean that only material written by REH is canon for Conan? Is only Bob Kane material canon for Batman? Is Frank Miller's Batman not part of Batman canon?
Someone official had to approve the changes, so I'm okay with that as well.