That's where the potential for speculation comes in. If you can buy Mtgox BTC and manage to extract it from Mtgox systems at some point in the future, you can m

That's where the potential for speculation comes in. If you can buy Mtgox BTC and manage to extract it from Mtgox systems at some point in the future, you can make a lot of money by buying for Satoshis on the BTC. On the other hand, if you buy these, MtGox never re-enables the ability to transfer the BTC they hold on your behalf into your own wallet, and then can't get someone else to take them, you're completely out of your original purchase capital. I don't think anyone expects MtGox to survive as a major player after this, but if you can get it out of their systems and into your own wallet, 1 BTC that's currently in MtGox is as good as 1 BTC anywhere else. What's being speculated on here is the confidence that MtGox will at some point restore the ability for people to transfer BTC out of their system, and the confidence that people will be able to extract (at current exchange rates) at least 20% of their BTC held there.