I'm taking delivery of an '11, auto, 4:10's and I noticed the same thing when I test drove it last week. I assumed it was because it wasnt broken in, which is what the dealer told me. My '06 with 3.73's and 35's has waay more pickup and if theyre all like that, I may just keep my old one, since its only cracking 90k.

 

My 07 5.9 stick with no mods (yet) gets going really fast even pulling my 14-15K 5er trailer. It even twists the front as one accelerates. It revs out quick in 1st/2nd.