Based on what I've read on a number of sites, I'd say Dodge is actually listening to us (to some extent) and dropping some of the "creature comforts" for more "performance inspired" additions in the Challenger.
The Challenger comes with full curtain airbags - standard, where the Charger does not.
The Challenger has a sportier suspension in R/T trim than the Charger.
There are more differences between the two.

You'll need to read carefully to find all of the subtle differences....but it does make interesting reading.