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Plug your iPad into iTunes, right click on the device (listed on the left of iTunes) and click "transfer purchases" and also back up the iPad. The apps should show up under the "applications' tab right above your "devices tab" on the left of ITunes

I just tried this with two games and none of the data was saved. The only way I can think of saving data is to restore a backup in iTunes/iCloud, but that's unnecessary when I just want to save the data from one app.
 
This is my biggest fear, I haven't bought an ipad yet (I plan to), but I've always bought the smallest iphone, mostly bc I don't download a lot of aps. But I think if I got an ipad I would do a lot more movie watching and game playing than I would on my iphone. I think when i decide to buy I'll go with the 32 gig just to be safe even though its going to hurt me int he pocket.
 
I don't think iCloud will allow you to back up the data in applications...that's just my hunch. Maybe, the general itunes backup, but to access that, one would have to restore from backup to do that. Then again, that might not work either.
 
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