If you're an international user who just picked up an iPad in the US and want to get some apps via the on-device App Store app, you 're out of luck: "Cannot Connect to the App Store. The App Store is not supported in your country"
That's what you'll get if you synced via iTunes on your Windows PC or Mac using an international account, like Canada, Australia, UK, etc. and then try to use the iPad App Store app.
Of course, you can just keep on syncing via iTunes but for the convenience of the on-device downloads, you'll need a work-around.