I thought Dodge offered a suspension upgrade for the '08 - '09 Challengers in the performance catalog... I downloaded it and searched, though, and couldn't find it.
Looking at the threads, though, it's obvious a lot of guys are lowering their cars, especially the R/Ts. Several aftermarket kits are available, with varying degrees of drop and performance. I opted to replace the front springs with ones from the SRT8, and I'm satisfied, although I will probably replace the sway bars front and back, add the strut tower brace, and swap out the brakes for the SRT8 Brembos... I don't race the car, but there are a lot of twisty-turney roads out here I would love to tackle with a bit more gusto...
I think it would be nice to have one offered by Mopar, and covered under the warranty... like the cat-back exhaust system (made by Corsa).
The Popular Mechanics Challenger make-over
Eco + Muscle: 2009 Your Drive Makeover
used a combination of a Pedders/Bilsten kit and one from Razors Edge. Now that's probably more of a performance-oriented kit than most of us would want to have to pay for, but it seems to me Dodge could come up with something close to that level of performance at a reduced price, and offer it as an option...
I'd buy it...