That would drive me bat shit crazy.
I vote for a new truck if you are considering that option. Here's my logic:
1. I don't like buying the first year of a new truck. You end up paying more due to limited rebates/incentives which results in a greater depreciation hit when it comes time to sell. Some people mention the first year bugs but my decisions are usually purely financial.
2. I keep a truck 3 years on average. Buying a '12 should keep me content until around 2015 at which point the new design will be out for a couple years and rebates will start hitting.
3. Current rebates and incentives are crazy. I bought my '08 brand new, drove it 4 years and was able to negotiate a trade in price that was only $6 less than I paid for it brand new. $1,500/yr to drive a new vehicle is pretty good IMO. In addition, the dealer came down $13k off the price of the new '12 Denali I ended up with. I can PM you my exact deal if you are interested.
It's a toss up between a Denali & LTZ/SLT. Pros/Cons for me:
Denali
Pros - Nicer leather, perforated ventilated seats are now standard, back-up camera standard, priced about the same as an equally optioned LTZ/SLT, & slightly better resale (in this area anyway)
Cons - full-time AWD (I prefer 4WD so I can play in the snow in 2WD

), chrome overload (wheels, door molding, & door handles).
LTZ/SLT
Pros - 4WD (instead of AWD), the wheels aren't quite as ugly, painted door handles
Cons - the leather isn't as good of quality, pricing is close to the Denali if optioned the same, resale will be less than a Denali (again...that is the case in my area...could be different elsewhere).
At the end of the day, you can't go wrong with either. It was a coin toss for me.