There's been an ongoing effort on reddit to collect relevant addresses:
http://www.reddit.com/r/Bitcoin/comments/1z14j0/needed_any_bitcoin_addresses_you_have_used_to/Needless to say, there are quite a few interested in gaining some insight into what
really happened.
There has been very little evidence of duplicated tx's by mtgox, certainly nowhere near enough to account for even a tiny fraction of 850k coins. The true story is right there in the blockchain of course, but there are just too many pieces missing (i.e. mtgox cold storage addresses).
Mtgox undoubtedly knows the true story, but clearly are either not willing - or at liberty - to make anything but vague statements.
"bitcoin days destroyed" stats point to large movements of long-stored coins at a few recent mtgox-related dates.