You think maybe it's a darker ash cap? Try popping it off for a sec. Is it still dim?
I was a little irked when the new USB chargers were dimmer, but it looks like the LED is inside translucent black plastic now, instead of out in the open, like the old green LED ones.
Well glory be! I didn't know you could take those off. Okay I took off the ash cap and it's still dim. I don't have another purple one but took the ash cap off a manual with a blue led. It's much brighter with and without the cap than the purple one is.
It's not a big deal to me because the new batt is really great. Just thought I'd let eyebedam know I had a dim one too. Battery, that is.

don't sample said new flavor after having chimichangas for dinner 
I was starting to wonder
Especially since it has been up a couple of days now . . .