I have already mentioned this issue in the official MtGox IRC channel but would also like to bring this to the attention of the greater community in general as well.
I find it mildly astounding that while we are all using a transaction network which is based on total transparency as one of its greatest assets in its very foundation, people are conveniently willing to give up on this very right (yes, I think it is my right to know where my bitcoins are coming from) by exchanging their bucks in open exchanges for potentially unaccounted for bitcoins.
Considering all the bad news about bitcoin lately, I think it would be in the best interest for overall bitcoin legitimacy to make use of the network's already existing transparency and link all virtual trades to actual bitcoin transactions.
Not only would this help track down stolen coins more easily, but it would also ease many people's minds and concerns as to where exactly those 10s of thousands of bitcoins come from that get poured into the markets on a daily basis.
I think this needs to be addressed somehow and has to be implemented in one form or the other - as such I'm even willing to pledge 10BTC for its development so people start taking this issue more seriously. Perhaps other people are willing to commit to this issue as well, but generally I think this actually has to happen with or without any pledges (especially if it can be established as some form of standard for any legitimate bitcoin business that works with virtual, non-directly bitcoin backed user accounts).
Perhaps we can get some MtGox, Tradehill and Camp BX (non-exclusive list!) officials to post their stance on this issue.
Thanks for reading, now fire away! edit: I am mostly referring to internal exchange sites transparency, as in I purchase 10 bitcoins on MtGox and get a transaction ID which I can then trace back to a verified previous transaction in the bitcoin chain as an additional way to verify the legitimacy of said purchase without having to wait until the coins are actually being cashed out!