It seems new MacBook Air owners are experiencing strange behavior with the battery in the new MBA. While the expected usage of 3 - 5 hours is holding true, the time to charge the battery can be as long a 9 hours in some cases. While the cause of this strangely long charge time is for the moment unknown, it is the apparent randomness in the time taken to charge the battery that seems to be causing the most confusion. For example, running the MBA down to within a few % of 0 and plugging in the charger one can get an estimated time to charge from anywhere between 3.5 - 9 hours. It's weird....however, this forum posts claim after having charged the battery +10 times it settles down to a more reasonable 3-4h hours.