BGR has the deets on what appears to be an 8GB iPhone3GS entering the Rogers inventory system. If this is real, it will most likely mean the end of the iPhone 3G as we know it as there isn't much room ($149?) in the middle of the current lineup for the sole non "S" 8GB model. As Tim Cook mentioned at the last earnings conference call, Apple is having trouble keeping up with demand on current iPhone3GS models around the world.
More evidence below.