The warrenty issue comes up every mod thread. It could in some dealers and may not in others. All depends.. Ask your dealer first if you are worried. NO mod company will tell you yes or no.. It's up to you.. in the words of Clint Eastwood, " Do ya feel lucky, Do ya?"
At our dealer, it would depend who you dealt with, but sometimes the technician will blow the whistle if he dosen't feel like doing the work for warranty pay. In that case he would go to the shop foeman or manager, then your goose is cooked. Even I have to use only "certain" techs to do my work.
It's your lucky day! GM isn't selling many cars. Dealers are surviving on service revenue, at this point I think they are hard pressed to turn down even warranty repairs unless the mod is clearly a cause. It's all income to the dealer.
I would think one of the only things they could call you out on with an intake would be something related to the MAF. It's possible an owner could screw something up with it while replacing the intakes.