
Intel's CPUs can scale well. Most of them can scale all the way down to 800 mhz. And since most of them use roughly the same amount of power at that level, wouldn't it be better to use the more powerful CPUs in netbooks, etc.?
Think about this
My Fujitsu P1620 uses the Intel U7600 (10 w TDP) CPU, and max battery life at the lowest CPU level is around 6 hours for a 56 whr battery, so battery consumption of around 9 watts per hour.
The Lenovo x200, which uses a more powerful CPU (P8600, ~25 w TDP) and a bigger screen, can easily reach 9 hours battery life with a 9 cell battery (I am guessing around 10 watts per hour at most). We can easily see which is the better choice, performance wise: the x200. Not only does it offer twice the speed (2.4 ghz vs. 1.2 ghz), it can offer the same power savings when scaled all the way to 800 mhz.
Of course, everyone would want more powerful laptops with the same (or better) battery life. However, aside from the higher price, a netbook-sized laptop (10"-12") must also be designed so that it can dissipate the excess heat due to the more powerful CPU when running at full power. But I wouldn't mind paying $300 more for a netbook with the power of a regular laptop.