Amazon is currently showing the Motorola Atrix 4G for AT&T on Amazon.com at a list price of $599 USD. The Atrix 4G in a contract shows as low as $149 USD. No pricing has been announced officially for Canada, but if you would like to be notified, you can register with Bell Canada.
UPDATE: Source link to Amazon is dead, as it appears the Atrix 4G has been removed. We saw that coming… 😉