Ben Kuchera at the Penny Arcade Report seems optimistic about the possibilities for a PC version of Destiny. That's good, I suppose, given the number of people threatening dire consequences to Bungie on Twitter if they don't.
IGN's commentary around the ViDoc reveal was very pessimistic about the possibility, saying Bungie would only mention current and next-gen consoles, but Bungie's Pete Parsons has given PC owners reason to hope:
The interesting part is we, from the ground up, from the very beginning, we have made sure that [Destiny] can be on multiple platforms," Parsons assured me. "It's one thing to say it, it's another to design and actually architect for it, which we've absolutely done.
So there you have it: definite maybe.