On my new D3 I have noticed that to ajust aperture/shutter settings with the thumbwheels I have to first give the shutter a half press to shut down the image review for anything to take effect even though the meter is on and LCD displays are lit.
My D2x and D1x did not require this extra annoying action, although my D80 does (and is one reason why it doesn't get much use!).
Is there an option hidden away in the D3's menus that will resolve this matter?
I don't have a D3 to check, but what you describe is normal default behaviour for my D300 and D700. It was how the D2Xs and D200 that I owned previously worked, too.
However, there is an option to vary the Meter Off Delay, from 4 seconds up to "infinite". If you have it set to maximum, the meter always stays on, which uses more battery power but means you can use the Command Dials at any time. It's Custom Setting c2 in the D700, I don't know if it's the same in the D3.
I can use the adjustments while the top display is active, whether or not the image review is active. I have image review set to 20 seconds and the meter set to 16 seconds. The image review appears to activate the top display also so if I activate the image review the top display stays on for 36 seconds.