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I actually think the app will make it stay on. But I just turn of the autolock quickly by using the SBSettings (one of the best things about jailbreak imo). As for the alarm thing, I'm pretty sure that will still sound even if you turn off the screen as long as your still in the app (but then you won't get to see the awesome clock:D)

And yes, I already am tempted to buy the next gen iPad even though I know nothing about it :)
 
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