Probably, the biggest is that Tesla HAS been thinking about recycling. In fact, GF is build just for that. Likewise, they will be re-using a number of the cells from a 'spent' pack to run their GF, prior to recycling (which is cool).
How much does the battery cost to replace?
Unknown since it is not known how soon one needs to replace it. With the first round of the batteries in the MS (i.e. 2012 version), it appears that somewhere around 200-250K miles, is when the battery pack will be around 85% level. So most ppl think that it new packs will be needed around 2020-2022. At that point, it might costs 5K for a change.
Of course, with 200-250K miles on an ICE car, you will most likely have to rebuild the engine, along with all of that nasty maintenance.
Earth is a beta site.