I'm also new to the Amaze, and after a single conditioning, it seems to run down 100%-4% in about 18 hours,... then takes 5+ hours to charge. That's basically an overnight charge, when sometimes it's not convenient to have a charger at work, car, kitchen, bedside.
In case I acquire a spare battery, is there a charger/dock that could charge it without a phone connected? I've seen a few chargers for other, older HTCs, doesn't appear to be a single one that would fit the Amaze with its off-center microUSB port, but just something to charge a battery in would be a boon.