Given how kick-in-the-crotch fake the last supposed leaked memo from Rogers (the Canadian GSM monopoly and exclusive iPhone 3G carrier) was, I'm taking this with a Rockies-sized grain of salt. If even remotely accurate, however, it looks like:
In order to unbrick the iPhone in store (which is a requirement of the iPhone Sales Process), you must have iTunes version 7.6.3b4. Installed on your computer. This version has a special 'Activation Only Mode' that must be enabled and used in store.
For complete details, including the unbelievable but very Rogers-like ban on all forms of publicity, posters, and promotion (no advertising until 13 weeks post-launch?!), and more telco-related acronyms and contractions than you can shake your head at, check out the read link.