ok the last days the rumours about something odd with their prices really increased
there is insider trading or something going on
withdrawals with the TXID were seen in the block chain meaning it should be possible to withdraw soon. So people started buying the cheap coins. Thus price increased. Pretty simple if you read between the lines.
there are also news about artificial floor of the price
Regarding the floor there are also, and this is for certain, a sizeable number of speculators who have been transferring money into Gox by whatever means, fast or slow, they can, wanting to buy cheap coins. I think this week is when most of that money will be processed.