Rogers will not unlock the phone for you. Officially they don't unlock any phones under any circumstances, so the iPhone isn't really an exception in this case.
In principle, it should still be possible for somebody else to use it, if they either:
1) Already had an active Rogers account, or
2) Purchased some cheap-o Rogers prepaid phone, sold off the phone and popped the SIM card into the iPhone, or
3) Purchased a SIM-only package from a Rogers company store ($40).
The key here is, unless you (or the subsequent owner) hack it, it will still only connect to the Rogers network.
It ought to go without saying, that you'd still be on the hook for the early termination fee to cancel your own account before the initial 3 years are up.