It is a good idea
I recently bought an eee pc 1000HA and I find it an excellent tool. Laptops have always suffered from having short battery life and being heavy. Netbooks are light, and the eee pc 1000 series demonstrates that battery life can be 5 or 6 hours. The machine can do voip/skype/whatever and it runs a browser and SSH client nicely. Heavy word processors are over-rated, a lightweight word processor is good enough for most purposes.
Way, way, way, way back in the day there was a competition between x86, RISC, SPARC and PPC for the desktop: x86 won then but this is a market where competition could again have an effect and drive the price/performance ratio. Linux has an advantage over Windows in that it runs on x86/x64, also ARM, also pick your CPU. So do the vast majority of KDE & Gnome apps.
Therefore Linux has a competitive advantage in a market - netbooks - where the CPU price is extremely sensitive and (IMHO) there is real reason for competition against Intel & AMD processors. A portable OS applied to heterogenous hardware competing in a fairly common form factor could cause a (I hate to use jargon) paradigm shift.
Netbooks are already extremely successful, it would be very nice if they were adopted as value added marketing tools. Certainly with Linux there would be little likelyhood of vendor/OS lock-in: people would make RPMs or distros for the little beasties. A telco giving me a netbook with an ADSL contract would have a hard time stopping me or charging me for installing GCC, for example.
Problem is, they'll eviscerate the high margin Core2 & Phenom market. Then again, with 32 nm process tech soon ready and the small size of a netbook CPU, margins on netbook CPUs could be high enough to make up the difference.
If that is actually the case, who wants to bet a beer that Intel executes, AMD vacillates, and ARM & Fujitsu (sparc) & co. retrench ;-(