Any speculation on what the cost of delivery with this service will be (I'm guessing very few people currently take advantage of the 1-day delivery option, let

Any speculation on what the cost of delivery with this service will be (I'm guessing very few people currently take advantage of the 1-day delivery option, let alone same day, so I would guess this will need to be cheaper than those to be commonplace)? Also why is this better/faster/cheaper than just hiring someone to deliver things on demand ala TaskRabbit?