I'm growing weary of promises for new / better / cheaper technologies for ICT4D - whether it's the pure-touch-screen tomfoolery of the XO-2 or new designs from India (remember that they've been promising this since at least late 2006, and the XO-2 has been a diversionary tactic starting in 2007 and formally announced May of last year.
We're missing the point here, as usual. ICT4D is not about the ICT, it's about the "D" - Development. Use whatever technology is best suited for the problem at hand, don't wait on the next big thing or spend money to develop it, at least starting out. This is why mobile phones are such an attractive tool - amazing install base, even in the developing world, low cost, low-power, but provides limited connectivity and 2-way (limited) data flow.