its not the stabilitrac.
With almost 50,000km on my van, I haven't had this stumble for a while. It has gone away a while ago

 

I was going to reply the same thing. Our '07 is 2yrs old with 35,000 Km and I haven't noticed it for quite a while either.
Maybe that little "stutter" on the new Uplanders is part of the break-in procedure ??.... :0)