A lot of people are talking about the new MacBook Pro battery life, or more specifically the lack thereof. It’s actually interesting to consider the design choices hardware manufacturers have to make when designing portable gear, in this case weight is probably a driving issue because the new MBP is slightly heavier than the model it replaced.
The 20% reduction in battery life that Mossberg references is easy to explain, the battery itself is almost 20% smaller… the new MBP has a 4,700mAh battery while the old MBP had a 5,600mAh battery. Less battery capacity, less battery life between charges and it means less weight which slimmed down the overall package to be in range for the older generation MBP.
Much worse is the loss of battery life. When used with its discrete graphics processor, the natural mode for the kind of audience at which the Pro is aimed, Apple claims it will get just 4 hours of battery life, versus the 5 hours it claimed for its predecessor, which also used a discrete graphics processor. That’s a whopping 20% reduction in battery life.
More troubling is that as the battery degrades over time you will be more affected by the lack of battery power meaning you can likely expect to be replacing it sooner than the old MBP.