At least there is a retail replacement price, even if it might be considered high and unfavorable. Remember how long it took us to extract this piece of information from Nissan? Not long ago, they would apparently not sell a replacement battery at any price. Not a good situation either, at least from my perspective. While BMW markets their vehicles as "premium" and prices them accordingly, which may or may not resonate well with everyone, they do offer free maintenance along with a bumper-to-bumper warranty for 48 months and 50,000 miles.
I think this would go a long way to help LEAF drivers as well, and some of this coverage is available through add-on maintenance and extended warranty programs for a price. BMW warrants 70% of the original capacity for the duration of 8 years and 100,000 miles. We have not seen many degraded packs yet, mainly due to the fact that the i3 has not been on the market long enough, but the substantially better capacity warranty would signal higher confidence in the battery pack and its chemistry.
While I cannot say anything intelligent or reasonably quantitative about the SB LiMotive battery pack (joint venture of Bosch and Samsung), BMW stated that the cells have a hard core, which should translate to better longevity when compared to pouch cells. The cells an aluminum outer shell, much like what we have seen with Nissan, but they are much more rigid. While AESC cells are pouches packed in aluminum canisters, the SB LiMotive cell design resembles a solid brick.
I'm not sure which approach is better, and if there will be any difference between the two approaches. Once again, time will tell.