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Are you guys going to buy a physical copy of XY when it comes out? Or download it from the e-shop? I can't decide.
If you get it from the e-shop then you have it with you at all times, so can bring Pokémon and other games with you. Which is a huge plus. You can also get it at midnight on launch day.
If you buy a physical copy, you can stick it in other people's 3DS to trade for the inevitable third version. Also you're more likely to get it as part of a deal in a real shop than Nintendo's ridiculously overpriced store.