I think this brings up a very important question, one I doubt Rogers will answer.
Now that we can root the E911 phones, and now that we may possibly be able to load the Dream radio and keep our data... that means that we can all run versions of Android that are not the "officially approved" version Rogers would prefer we run.
Rogers made us upgrade because the previously existing version of Android we had suffered from a bug that could cause the phone to crash when dialing 911.
We know that the 1.6 and up ROMs have (or should have anyway) the fix in them, but Rogers wouldn't let us have data without either applying the E911 update, or signing a waiver.
Now that we can theoretically root and install a non-E911 OS version, and get data without signing the waiver... it stands to reason, logically, that Rogers must force another update to block root again and force another "official" version on us... otherwise they cannot justify cutting off data (or requiring the waiver) until/unless we have the E911 update, because rooting simply puts them back into that potential legal trap that existed because of the E911 bug.
It's a double-standard, just like allowing jailbroken iPhones on their network.