http://bit.ly/leafbatterydegradationmodel" onclick="window.open(this.href);return false;
Since some of the numbers didn't fit with Nissan's claims (even after they mentioned the "glideslope" in Arizona to 76% battery capacity remaining, and the fact that only 7500 miles were assumed for Arizona), I decided to see if I could tweak the model to fit TickTock's graph:

Here are my results (you may have to make text smaller in browser to fit on screen):

Summary:
Model fits the data from Nissan quite well using following assumptions:
Calendar loss first year without aging factor - 6.5%
Calendar loss slows with square root of time
Cycling loss per 12500 miles without aging factor - 1.5%
Cycling loss is linear
Boston aging factor adjusted to 0.75
"Normal" aging factor adjusted to 0.90
Phoenix aging factor adjusted to 1.35
Aging factors relative to "Normal" are:
Boston - 0.83
Normal - 1.00
Phoenix - 1.50
Note: while it might seem that my selections were random, or that many combinations could give the same results, I found that changing any of the values from this set of numbers caused increasing errors in predicting the numbers found on the graph. I make no claim that these numbers are good predictions of reality, only that they fit Nissan's figures closely.
