Gox's new trading engine and all of the upcoming exchanges (ex, Coinsetter) are completely unnecessary given the total volume on all current exchanges.
Prediction: 4-5 months from now, there will be at least a dozen new exchanges, most averaging about 1,000 daily volume. This "fracturing" of volume will ultimately result in lots of smaller and consequently more easily manipulable exchanges. Gox will still maintain the lead with 5,000 daily volume on the very busiest days. But, Gox too will be primed for manipulation given lower volume and depth.
Prediction 2: 1 year from now, after enough reports of manipulation and investors getting ripped off, the SEC steps in and requires exchanges to monitor and put in place restrictions to stop blatant manipulation (or at least make it much more difficult/risky). Bitcoin gradually drops in value to almost nothing as the community realizes the price is and always has been driven by whale-walls.
Prediction 3: Bitcoiners will die filling taxes. If one big whale wants to buy 1000 BTC, will need to do it in more than 10 different exchanges or suffer huge slippage. Many whales will die by accident next year when a sudden ton of paper falls over them filling taxes. Actually Bitcoin-QT client should include itself an exchange webserver and a bank account text box in the webpage.
Now seriously.
Exchanges are opening all over the world and some are designed as P2P, so it will be hard to put restrictions on that. There might be coming an arbitrage paradise for those willing to invest their time one APIs and their everchanging nature.