The FAA ruled in 2007 that US-registered twin-engined airplane operators can fly more than 180-minute ETOPS to the design limit of the aircraft. In November 2009, the A330 was the first airplane to get the ETOPS-240 approval. From Airbus:
The new capability will be available as a customer-selectable option which extends the diversion distance potentially up to 1,700 nm. This distance corresponds to a maximum ETOPS diversion time for the A330 of approximately 240 minutes (at one-engine-inoperative speed under standard conditions).
Here is the difference between an ETOPS-enabled shorter flight path (the solid green line) and a flight path for non-ETOPS aeroplane (the dashed blue line).