In Apple's words on Canadian website...
Version 1
http://store.apple.com/ca/browse/home/shop_ipad/family/ipad?mco=OTY2ODA0NQ
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Add a micro-SIM card from the carrier of your choice to your order and complete your purchase. You can also get a micro-SIM card later directly from a local carrier."
"Can I use my iPad while travelling outside the country?
You can connect to Wi-Fi networks in many places around the world. Check with your carrier about connecting to 3G networks outside your home country, as additional charges may apply. Or you can purchase a micro-SIM card from a carrier at your destination and choose a new data plan to connect to a 3G network there."
Version 2
http://www.apple.com/ca/ipad/3g/
"Choose your iPad by carrier.
If you decide on an iPad with Wi-Fi + 3G, be sure to select the model that corresponds with the carrier youd like to use for 3G service. The iPad model you purchase is specially configured to work with either Bell, Rogers, or Telus. So while you dont have to activate 3G service right away, you should choose your iPad with Wi-Fi + 3G according to the carrier you prefer.
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