I also own an iLiad. So far the biggest downside for me is the (bad to non-existant) power-management. And as you can see from some of my posts I am no fan of DRM.
the Sony Reader could also have the badge "Linux inside" on it. But there is one problem about adapting the device, so far there is no way of reflashing the iLiad without sending it back to the repair center and paying a 75 EUR fee.
And as everything is running as "root" on the iLiad, I wouldn't want to touch anything.