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When I read about this (and Ubuntu for Android) I was beyond excited: practically bouncing in my seat. I'm really glad they will be pushing out an install for the Galaxy Nexus since that's what I have. My concern is the pre-boot/recovery environment. Will I still be able to use ClockworkMod and all the backups I have on it? What if I don't like Ubuntu on my phone and want to switch back to a backup of my current ROM? I haven't seen anything about that yet. And while I rather enjoy the risky things you can do w/Android devices, this worries me more than normal.