Glad you're enjoying the new device! Please don't condition the battery on this one... Read my post in your other thread about your bricked 900 to see why.
I did, and I replied.
However I think I figured out what was wrong with the L900. Or at least MY L900....
So if you notice, the L900 takes a few seconds to recongize something is plugged into the mini USB port. I know that this happens on all L900's. It literally takes about 10 seconds before it will start charging or syncing with zune... etc.
THAT is the problem. When the battery is completely dead, and you plug it in, it tries to star the phone (white screen) then it realizes the battery is too dead to boot the OS (shows the battery status icon). The phone turns completely off (that is what NOKIA needs to FIX!) and it starts the whole cycle again.
Phones need to know whats plugged into it reletively fast otherwise it will try to boot the OS from a dead battery then realize it can't. That should be able to be fixed with a software update and hopefully Nokia does that.
They lost a customer because of it and I think I would easily consider the next Nokia device if they do in fact fix that issue.
Now I did say that when I used the Nokia provided power supply it did end up charging up. I think that's because the higher wattage is recognized faster by the device. They need a software fix for lower wattage chargers.