According to 9to5Mac, the new 2011 MacBook Pros are much higher powered than previous models. In fact, a total of 2100 continuous mA can be available at once. Great news for iPad owners, as this rivals the power of the iPad’s wall adapter.
The total power, as evidenced by the below image (credit: 9to5Mac), is significantly higher than previous generations, which only have 500mA extra operating current.
Source: 9to5Mac
