Assuming that Google gets its way and persuades the FCC to allow White-Space Devices (WSD's) (assuming the prototypes "pass" the tests), I just realized another serious problem.

If we can cast aside doubts about adjacent channel interference (which I can't do) and a myriad of other concerns, it seems that even a 1W WSD within a few hundred feet would be enough to overload most pre-amps.

Can anyone run some simulations on how far away even a single WSD would need to be to not overload a typical pre-amp?

Since pre-amps are typically used in fringe areas for TV reception, would these areas essentially be giving up TV reception to get the Internet from a WSD?

Some have proposed that White-Space devices (if ever allowed) would need to be band-limited. I agree with this (if they must be allowed at all). However, the only area that seems suitable is Low-VHF. Something tells me that Google wouldn't be very excited at the prospect of WSD's having 5-8' antennas.

You better also worry about CH52-69 high power fixed site and lower power
mobile devices. At least they could be countered with a low-pass filter.
Qualcomm decided to put a 50 kW transmitter only a few miles from me,
and scattered them throughout L.A. and San Diego.
Other 700 MHz band users may do the same...or worse...

And don't forget FCC OET found that nearby WSD devices readily
leaked into Cable (and some SAT) frequencies via the LCD itself:
http://www.fcc.gov/oet/info/documents/reports/DTV_Interference_Rejection_Thresholds-03-30-07.pdf
Leakage is probably even worse for USB Sticks and (plastic case)
HDTVs not as well shielded as the mostly metal LCDs tested to date.

THERE ARE NO WHITE SPACES ON CABLE...