In a related convergence, Russel Beattie writting about celphone/moblie technologies notes :
There’s got to be a tipping point where Powerful or Possible technologies become the Practical day-to-day items.
I might dispute the “got to be” (because there is no “right” for any technology to succeed; “should” is not “would”), but I agree with the intent : technologies only become main stream (dare I say Commodities) when they move beyond possible and become practical (and then become useful). Camera phones are there. Digital music players are there and got there before DRM started to get in the way. Ebooks are not (yet) and DRM slowing their emergence into “Practical” and/or “useful”.