Well, looks like I was wrong about the price of ProtoShares... the thing that I did not take into account was that the AngelShares donation scheme has a direct BTC donation mechanism. So people can buy into the BitShares distribution without having to hold PTS, or convert their BTC to PTS. Donations have been around 150 BTC per day for the past week or so. If those BTC had to be diverted through the PTS markets, the price of PTS would have gone way up.
So, expect the PTS price to crash later today after midnight GMT (roughly 7 hours from now). But you'll be able to import your PTS wallet into the BitShares wallet when it is released, and get 1.3 BitShares per PTS owned of record tonight. Just think of it like a stock that's just gone "ex dividend"; it still has value, but less value than before the dividend.