Victoria's Secret (LB) has used the Free Shipping offer as an offensive weapon in the past (they were one of the first to do so, actually), but this is a continuation of a trend that we think will ultimately plague the rest of retail.
While LB is a high-end brand with a very loyal customer base, we would note that even a powerhouse like Victoria's Secret can't easily absorb free shipping costs due to a relatively low average basket size.
It's high-ticket retailers like Nordstrom (JWN) and brands like Nike (NKE) and Ralph Lauren (RL) that could absorb shipping costs without a material hit to their margins.