I was at Toronto Comicon this weekend and my best friend was freaking out over the multiple Star Trek actors. The night before John DeLancie's panel, she told me he was Discord's voice actor (I hadn't a clue before hand).
I went up to him to get a picture of Discord signed by him, and he started to laugh, talking about the lack of females approaching him. I was the only one to mention MLP to him and it must have amused him, because he told me a little spoiler~!
Guess who will be returning to MLP:FiM~~??
(He also told me that despite voicing Discord, he never even watched the episode, and that he would watch it when he was done at the convention.)
adjusted thread title slightly ;) OL1
tl;dr - some girl met John DeLancie at a panel, Discord's voice actor, and he dropped her a little spoiler that he is returning.
I never trust forum posts, really, but you never know. This was posted yesterday.