Be interesting to see how quickly ICS is adapted by the public at large. I mean it'll be interesting to see how quickly Android 2.2 and 2.3 devices are upgraded to Android 4.0.
Just my opinion, but most phones won't have the horsepower to run ICS and the carriers are always loathe to spend manpower porting a new release to a old phone when what they really want is for you to buy a new phone an re-up for another 2 years.
Upgrades are why I really appreciate the developer community, doing hard work that vendors drag their feet with.