How long is battery life on the Apple Watch?

UPDATE: Apple CEO Tim Cook said the Apple Watch will have up to 18 hours of battery life in a "typical day".

Apple has not yet provided specifics on the battery capacity or expected battery life on the Apple Watch. The charger was highlighted, featuring MagSafe technology with inductive charging. This makes the Apple Watch easy to connect for charging, even in the dark, or while "only partially awake".

The verbiage from Apple's website and other hints from Apple point towards the Apple Watch requiring a nightly charge. This could mean the Apple Watch battery only lasts for 12 hours. Stay tuned for the official word from Apple when Apple Watch is released in early 2015.