I'm sorry but in my book, both platforms suck. 0 performance and yet rather high power consumption.
My IBM X60 drains below 15W idle with wlan and Bluetooth enabled, and that's with a 12" screen, rather strong Yonah Dualcore and 2Gigs of ram.
Of course it costs 5x as much, but the old rule still applies I guess.. what you get is what you pay for ^^

The power drain of either Atom or nano platforms are ridiculously high in any case. Of course, hothardware's measures are incorrect as always. You won't get under 30W idle though, which is still 3x higher than it should be.