The new weight is immediately noticeable as soon as you hold the PSP in your hand. It's so light that you might think that it's missing a battery or doesn't have a UMD inside. Sony was able to slim down the battery size while maintaining the system's 5-hour battery life by decreasing the power draw of the unit. You'll be able to use old batteries from the original PSP to double playing time, but the standard battery cover won't be able to fit over it. Sony will offer a high-capacity power kit that will come with its own PSP cover to fit over the larger battery.