I've seen several references in other posts concerning USB charging not working. My Galaxy Tab charges fine while hooked up to my laptop with the USB cable. I wouldn't think it should matter which version you have (I have an unlocked German version). Just an FYI.
I just bought a Galaxy Tab 2 7.0", and noticed that it charges perfectly thru USB cable while its off; but when it's on, it doesn't charge.
I have a Galaxy S2 also, and it does charge thru USB cable when it's on.
Does anybody knows it this is possible on the Galaxy Tab??