It does not use a standard micro USB port according to the PC Magazine Review:
From the article:
"Make sure you bring your charger wherever you go. Although the Nook Color looks like it has a standard micro USB port, it will only charge with the Nook AC adapter. I tried both 5V and 10V adapters, with no luck. Nor can you charge the device by connecting it to a PC. Turns out the cable that comes with the Nook Color has a few extra pins in it, to enable faster charging. The custom connector supports 2000mAh charging, whereas most mobile electronics use 500mAh chargers. This is limiting, since it significantly reduces your charging options, but it isn't much different than the proprietary charger that's required with the iPad."
Officially, you can only charge with the provided charger and cable, and also the NC won't tell you it's charging if you plug it into a USB connection. The documentation and whatnot warned of this. HOWEVER, if you do plug it into a usb port, using the provided cable or a generic one, it will charge. I've done it myself. It won't tell you it's charging, but come back an hour later and you'll see that it is. The reason for these discrepancies seem to be mostly due to the high capacity battery that takes 4-5 hours to charge even with the included fast charger.
It probably will drain faster than it's charging if you use it while it's charging this way, however. Also, the documentation warns that using any other type of charger (like the one that comes with the original Nook) could damage it. I doubt this is really true, since it is probably just delivering 5v just like the USB port, but be forewarned.
There's a silly trend in economics that forces you to use proprietary connectors and chargers. The manuacturers know that people lose these things , and so are forced to spend stupid money on replacements. Simple, simple economics. I made the mistake of purchasing a Sony digital camera with a proprietary USB connector. It will cost me 38 bucks to replace it if I lose it.
IMHO, this is another reason, I will not migrate over to the Color, away from my Classic. I can charge with any microUSB charger.
Doesn't anyone ever read the instructions?
Nookcolor can only be charged by the charger it came with.
I think what the issue is that you can normally plus any usb into an adaptor to charge. They managed to go all Apple on us by charging $25 for a $3 car adaptor.
If I plug the Nook Color cord into my iGo Green wall charger's USB charging port, the Nook Color charges, If I plug the Nook Color cord into the iGo charge anywhere it will power the Nook Color. But the iGo line of power supplies is designed for charging only.
Powering off the Nook Color seems to let lower powered power sources charge the Nook Color.
Now use of a different cord may be an issue because of some special wiring within the Nook Color cord.
This policy maybe why the Nook Color has issues when used in the EU. The EU is trying to establish a limited number of power tips for charging cell phones.
B&N may not replace the Nook Color if they can show you did not use their power cord and power supply.
There are lots of discussions concerning the special charging micro-USB connector and cable for the Nook Color.
Here's the deal - the normal USB port or charger produces 5v @ 500ma. The Nook Color AC adapter can produce 5v @ 1.9A (1900ma). Actually, any charger will work ok, it just takes longer to charge the battery... the more "amps" the faster the charging rate; bigger bucket filling the bathtub.
To handle the extra current flowing to the Nook Color, the special micro-USB connector is "longer" and has an extra 12 pins at the tip, that go deeper into the special micro-USB connector on the Nook Color.
A normal micro-USB cable can still be used for data transfers or slow/trickle charging, since it will only go in the normal depth and not make contact with the deeper special pins.
Here's a photo of the special extra long micro-USB connector....
Notice the extra 12 pins at the tip - vs just the normal 5 pins...
That is why this cable will NOT work charging other micro-USB devices,
but the charger works just great when used with other normal USB charging cables.
So - when on vacation or travelling - I just bring the heavy duty Nook Color AC adapter, the Nook special micro-USB cable, a normal/standard micro-USB cable, a mini-USB cable, and finally an ipod/ipad USB cable..... So, one heavy duty AC adapter for USB & all the different cables.