"Most of the people using PowerPCs are even on Leopard."
I am a visual effects artist & animator
upgrading My OS right now would break
several very expensive 3D & VFX programs requiring me to
$$upgrade them as well$$
Cant afford the Expense &I dont need the latest OS to be productive for my current Client Database.
Beside the point anyway.
The kindle fire does not need a separate "gateway" Application( ala itunes) on our PC's& Macs as it would
be a restriction for users who want to forego the "cloud" and sideload content IMHO.