Here is my defense of 5 Ghz: The 5 Ghz band for 802.11n CAN be significantly faster than the 2.4 GHz band. By using channel combining on the 5 GHz band, you can achieve a bandwidth of 40 MHz, as opposed to 20 Mhz on the 2.4 GHz band. If your dual-band router supports channel combining (most do), your new N7 will in fact honor this setup and perform at the higher bandwith and throughput. It's part of the 802.11n standard.
In addition, the 5 GHz band is MUCH less crowded, further improving throughput and reducing interference. Not only is the 2.4 GHz band crowded with tons of wifi, bluetooth is on this frequency as well, and it interferes with wifi. As do many cordless phones, and much of the wireless home theatre wireless speaker links (ie: Sony S-Air system). The list goes on and on.
I personally have found that many articles suggest going to the 5 Ghz band at home, when possible, and there is already a push to migrate to the new AC standard (though there is a dearth of AC mobile devices so far).
In my own personal home experiments, using my 50 mBit/sec Comcast connection and a (used to be) high-end dual band Linksys wifi router (WRT610n), I'm getting almost triple the throughput on my 5 Ghz band using the new N7 as I do using the 2.4 GHz band (at closer ranges), all other things being equal.
Does 5 GHz attenuate (drop off) more quickly at distances than 2.4 GHz? Yes, after all, everything in life involves tradeoffs. Yet, with a high quality MIMO dual band router and proper placement, the attenuation can be reduced. I have 2500 sq. ft. of living space and reach all corners pretty well at 5 GHz. Your mileage may vary. Neall